Manuel Insua, 22, speaks no English. He has no job, no car, no home for his wife and 2-year-old child. He is not a bit worried.

"In the United States," he says, "you can overcome anything with a little sacrifice. There is no poverty here. Anyone who wants to work can work. I want to be a millionaire. It will be difficult, but not impossible."

The Amercian dream is alive and kicking in the hearts of the nation's newest refugees. More than a third of the 30,000 Cubans who, like Insua, have poured into south Florida in the last three weeks are already settled in the homes of friends and relatives.

Hundreds have found jobs as factory workers, secretaries, waiters and janitors, and the rest are out looking. They are snapping up Social Security numbers, studying driver's education manuals and poring over English textbooks.

The brimming optimism of these destitute refugees may seem incongruous to a country battered by inflation and sliding into recession. But if the experience of Cuban exiles is any indication, these new immigrants are likely to be rapidly absorbed into the nurturing, bustling Latin communities of Miami and other cities.

"These people will get the jobs everybody else doesn't want," said economist Ray LaCombe, a Miami banker. "But from past experience, we've seen that they are very industrious. They'll work and they'll work hard and they'll get ahead."

More than three-quarters of the new arrivals have relatives in the United States. Refugee aid groups say that so far they have more than enough sponsors for the others.

However, the economy's absorption of the new immigrants will be more difficult as the numbers escalate -- some U.S. officials fear as many as 250,000 could flee Fidel Castro's regime in coming months.

Florida, which has a population of 500,000 Cuban exiles, is where most of the new refugees would like to settle. About 40 percent have relatives in Miami -- Dade County alone and they feel comfortable in a city where Spanish is spoken as much as English and where the schools and government are officially bilingual.

However, while the Miami area has a low unemployment rate -- only 4.9 percent in March, the last figure available -- it has a housing squeeze, with less than a half of one percent of all units vacant. The English-speaking community by and large has welcomed the new arrivals, but there are strong feelings that Miami is already Latin enough.

Gov. Robert Graham advocates "resettlement outside Florida . . . for those Cuban refugees who do not have family in Florida." Cuban leaders here, fearing a backlash among non-Latin whites and blacks, agree.

The debate over the new refugees has not reached the ears of Manuel Insua. He is too busy fashioning an instant future.

Since he arrived here April 21, Insua and his wife, Mirna, 18, and their son Jemmy, have been sleeping on a mattress in the living room of the cramped one-bedroom apartment of Mirna's aunt and uncle.

"It is very difficult," said the aunt, Flora Oliva, who lives in a squat pink stucco apartment building typical of the Cuban neighborhood of Hialeah. Oliva said she will have to put the Insuas out when her daughter and three grandchildren arrive from Cuba any day.

On Saturday the Insuas spent nine hours searching through the heat of Miami for an apartment. All were $280 a month and up, more than they could possibly afford, especially with the required deposit amounting to two months' rent. Many landlords refused to accept children.

Yet walking into his aunt's apartment after the long day, his blue jeans and T-shirt dusty, he said, "I'm so happy. Even if I live in the worst place in America, I'll be full of joy here. What I like is liberty. In Cuba I lived in fear."

Insua, an irrigation technician in Cuba, has already applied to a grocery store, a department store and a constuction firm for jobs. They told him to come back when he had a Social Security number, which he quickly obtained. tHe plans to reapply today.

But his ambition is to go to Alaska as soon as he learns English. "I heard you can earn a lot of money there. I can stand the cold for awhile. I am strong," he said.

He doesn't mind leaving Miami's Cuban cocoon."Here Americans are harder to find than a needle in a hay stack," he said, laughing. "I want to be with Americans. They are very refined, very educated, very normal. I want to be an American."

Alvaro and Greta Insua, who, along with Manuel's grandmother and great-aunt also arrived two weeks ago, laugh at their son's excesses. But they are hardly less zealous in their affection for their new country.

"I see a rosy future," said Alvaro Insua, 44, a former statistics professor who spent six years in Cuban forced labor camps. "Even if I don't find work or a home or the sky turns gray, we're still in a free country."

Yet the older Insua is not rebounding quite as fast as younger refugees. "I am still very nervous, unbalanced," he said, his hand trembling slightly. "When I walk out in the street, I still think someone is following me. It's hard to get rid of the mentality."

Miami health officials working with the newcomers say many are suffering from physical and psychological abuse that will take weeks, months and, in a few cases, years to overcome.

However, the majority, even those without friends or relatives here, seem remarkably ready to adapt. The day after Jose Abreu Gutierrez, a 27-year-old printer, arrived in Miami, he awoke in the St. Agatha's Church Refuge and walked over to a nearby Burger King to cash a $40 check given to him by a Cuban exile group.

The manager, whose name he said is "Juan," told Abreu Gutierrez he couldn't cash the check but he could give him a job. The next day, the Cuban was standing proudly in his brown and yellot Burger King uniform, frying potatoes for $3.10 an hour.

"In Cuba, I got $95.30 a month," he said. "Here I earn more than that in a week."

Abreu Gutierrez has made new friends among his mostly Cuban co-workers, has visited their houses and marveled at their possessions. A Cuban-American customer drove him around the city, gave him a watch and promised him a car as soon as he learns how to drive -- the kind of generosity occurring daily as the city opens its arms to the new refugees.

In another corner of the shelter, Reinaldo Morales Silva, 36, is studying his driver's manual as a dozen other refugees watch "King Kong" on television. A former leathercutter, Morales Silva has worked three days at construction since he arrived two weeks ago. He has no permanent job.

But in the Spanish Yellow Pages under prices -- leather -- Morales Silva has made a checkmarks next to the factories he plans to call. Meanwhile, a new acquaintance has offered him a job in a car park when he gets his driver's license.

"I don't know where, but I know I'm going to work," he said.

Morales Silva arrived with only the clothes on his back, but already he has acquired two suitcases full of attire, and a set of new pots and pans, gifts from the community. He has no relatives in the United States, and the friends of friends he telephoned in New Jersey did not offer help.

"I have a lot of sadness because the Cuban government did not let me bring my wife and child," he said. "But someday I hope they can come. Until then I will look for a way to live, quietly, with liberty."