Colombian President Belisario Betancur, speaking with what he called "blunt frankness," told President Reagan today that the United States should shift its policies in Latin America to reflect "the reality of the continent as it is."

In one of the sharpest toasts ever delivered to Reagan by a foreign leader, Betancur called for an emergency economic plan to rescue Latin countries from their foreign debts, a new social alliance respecting the rights and needs of Latin American nations and elimination of the "exclusions in the inter-American system," an apparent reference to Cuba's exclusion from the Organization of American States.

"We cannot deliberate calmly over abstract problems in our hemispheric organizations when in certain parts of Central America bonfires are lit by social injustice or provoked by foreign hands that do not belong in the area," Betancur said.

It was unclear who Betancur included as "foreign hands" but the Colombian position on Central America is that all foreign intervention should end to prevent the region from becoming a focus of East-West conflict.

Reagan's visit here lasted five hours.

The critical tone of the reception for Reagan here was in considerable contrast to the good will evident in Brazil, which was cemented by Reagan's announcement of a $1.2 billion loan to help that country's hefty balance of payments problems.

Anti-Reagan slogans were scrawled on downtown walls along the route of the motorcade from the airport into Bogota and there were unfriendly shouts at his only public appearance. Crowds were kept 100 yards away by riot police while Reagan laid a wreath at the statue of Simon Bolivar, the foremost hero of Latin American independence.

Reagan supporters near the front of the crowd cheered, but others in back whistled and shouted, "Out, Out."

Betancur, who took office Aug. 7 after winning an election in May, has appeared to move away from his country's past close alignment with the United States and has sharply attacked U.S. support for Britain in the Falklands war.

At a luncheon at Casa de Narino, the presidential palace, Betancur warned that because of economic problems, Latin America "could see itself swept along by social forces to declare itself insolvent, producing reactions which no one desires."

Betancur proposed that the foreign debts of Latin nations be renegotiated, that their payments be limited to a fixed percentage of their export earnings and that international aid organizations such as the Inter-American Development Bank and the World Bank step in to take a more aggressive role.

On this point Betancur said that his proposal "deals with the necessity of a change in the position of the United States" in its contribution to these organizations and added that there should be "greater dynamism" in negotiations between the United States and Colombia over such key Colombian exports as flowers, sugar and leather.

"This frank and cordial visit could reestablish the terms of political exchange between the United States and Latin America that have deteriorated considerably ever since the still-unresolved problem of the Falklands, in which the region was neglected," Betancur said.

Reagan, who delivered a flowery toast to President Joao Figueiredo in Brazil Wednesday and received some blunt words in response, sharpened his remarks today after his staff learned that Betancur planned to speak frankly.

"We changed about two minutes of the Reagan toast to make it more matter of fact," said one senior U.S. official.

Reagan tried to strike a conciliatory tone.

"I just want to let you know how much I appreciate your frankness today," Reagan said. "I know you were speaking from the heart, and I can assure you that we were listening closely. One of the great traditions of democratic nations, as you know so well, is that leaders can speak candidly to one another and accept the other's thoughts in a constructive spirit.

"You have spoken frankly," Reagan added. "Now let me do the same."

Later, en route to Costa Rica, U.S. Secretary of State George P. Shultz acknowledged that "it was a tough toast." But deputy chief of staff Michael K. Deaver said later in San Jose that Reagan had expected blunt language from Betancur and was "not offended or put upon."

Deaver said that Betancur told Reagan in their private meeting that every U.S. president had come down to Colombia to tell the people there what to do. "I agree with you, but I have come down to listen," Deaver quoted Reagan as replying.

Shultz said that Reagan agreed "in principle" with Betancur that Cuba should be part of the American system, but "only if it breaks its ties and ceases being a satellite of the Soviet Union."

In an apparent answer to Betancur's criticism of regional organizations, Reagan said that Colombia "has long been a powerful supporter of the inter-American system," and added that "with few exceptions, this system has kept the peace."

This year both Colombia and Venezuela have petitioned to join the Nonaligned Movement. Shultz described Colombia's action as "moving in the direction of the Nonaligned Movement" and said "the U.S. would have some things to say about that" in the private meetings held today between leaders of the two countries.

U.S. officials also had something to say about illegal drugs. Colombia is the major source of refined cocaine entering the United States, and the Reagan administration has sought the cooperation of Colombian authorities in cutting off the narcotics flow.

"We recognize that the use and production of illegal drugs is a threat to the social fabric of both countries," Reagan said. "I am determined to control and reduce drug consumption in my country. Progress that either of us make will assist the other."

Colombian officials have looked upon drug production and traffic, which fuels a significant parallel economy here, as less of a threat. They emphasize that the drugs would not be coming into the United States unless U.S. consumers wanted them and compared the U.S. efforts at control with Prohibition.

Colombia has avoided many of the economic problems of its neighbors. It has a relatively small foreign debt, and, unlike the majority of Latin American countries, expects to have a positive economic growth rate this year.

Under Betancur, Colombia has approached the problem of leftist insurgency by offering an unconditional amnesty to members of the country's five guerrilla groups and established a special commission to negotiate with the insurgent leaders.

Shultz said today that "the offer of amnesty seems like a constructive thing to do . . . and I wish them the best of success with it."

Colombia has not sought U.S. help in dealing with its longstanding insurgency problems, even though the Reagan budget for 1983 provides Colombia with $12 million in military assistance.

Security was tight today, reflecting concern about a repeat of a demonstration here Thursday in which the U.S.-Colombian Binational Center was stoned. Today, students battled police during another demonstration at the Colombian National University, and a labor rally to protest Reagan's visit was scheduled to follow his departure.