Fuad Shili, 20, a Palestinian commando from the occupied West Bank, lay on the slanting concrete ramp of a shell-shattered apartment building's underground garage today and said that when his orders come to evacuate West Beirut he will do so, like any good soldier.

The braying of a donkey punctuated the stillness that hangs over the no man's land separating the Beirut suburb of Burj al Barajinah from the positions of the Israeli Army 200 yards away. "If Yasser Arafat says that I must go out, I will go out. If he asked me to stay, I stay," Shili declared.

Like virtually all of his fellow combatants from the Palestine Liberation Organization hunkered down in positions from which they have fought the Israelis, Shili said he had as yet received no direct orders to join the U.S.-negotiated evacuation that is scheduled to begin Saturday.

"I don't know where I will go when I am ordered to leave," the unshaven Palestinian told a visitor. "Anywhere they say, I go."

With a knot of fellow guerrillas nodding assent, Shili made clear that when he did leave he would go proudly. They held the Israelis at the periphery of the Lebanese capital for 69 days, he said, despite that Army's firepower.

Fuad, and dozens of other PLO fighters visited in their front-line positions today, contended that the siege of West Beirut was but one battle in a wider struggle that will go on until the Palestinians -- who have been homeless since the creation of Israel in 1948 -- have their own nation.

"I am a Palestinian commando and I will remain one no matter where I go," he said. "I will not go back to life in a refugee camp like the one I grew up in. What we won here was our right to go out of here alive with our leader, Yasser Arafat, so we can fight another day."

In a gun-strewn lobby of an apartment building in Bir Hassan, a southern Beirut neighborhood where the Israeli advance up the coast ground to a halt, a 45-year-old guerrilla-accountant said he had no intention of leaving Beirut at all. As a refugee from Palestine in 1948, Abu Khaled (a nom de guerre) said he had Lebanese citizenship and thus need not evacuate with the 7,100 PLO fighters.

"Where do you want me to go?" asked Khaled, a gaunt man, with a small pistol holstered on his belt. "I have nowhere to go but Palestine. I will stay here until I can go home."

Khaled said that of the 11 members of his immediate family, five more were PLO fighters: his wife, two sons, one 16 and the other 13, as well as two daughters, age 18 and 17.

"We are ready to fight Israel a million times more for the right to go back to our land," he said. "It is just not me that will continue fighting, but my sons and my sons' sons."

As Lebanese Palestinians, Khaled and his family plan to wait here until they are called to arms again. "I will not give up my rifle," he said. "I will keep everything I need to fight Israel again."

There are perhaps thousands of Palestinians with Lebanese passports and identity papers who plan to fade back into their normal life in the city, returning to previous jobs, businesses or university campuses.

With the expected beginning of this new exodus of the Palestinians but hours away, there were few signs that the promised departure was finally at hand. In downtown Beirut, most PLO fighters defending strategic corners or ambling in the streets with their rifles professed ignorance of just when they were to depart.

"I know the PLO must get out of Beirut," said Abu Jahid, 31, a member of a 100-man PLO unit in Burj al Barajinah. "But when we go, we have not yet been told."

The word to the first evacuees went out today. PLO sources said the first to embark on ships Saturday would be some 400 fighters destined for Iraq and Jordan. Sources said they would gather at the municipal stadium in West Beirut and be driven to the port of Beirut later in the day after 350 French paratroopers arrive there.

A sign that preparations were under way was the sound of explosions in the southern part of West Beirut as PLO fighters detonated land mines on beaches and roads to make departure safe. PLO offices were being stripped of files and even some of their propaganda posters.

An official of a PLO organization said his office's files had been burned but information that would be needed for the new headquarters, probably in Damascus, was on microfilm that would be taken out.

The once tense and ugly mood in the streets of West Beirut had given way to an almost holiday atmosphere along the traffic-jammed Hamra Street in the business district. Although many of Hamra's fancy shops and boutiques remained shuttered, hundreds of small businesses selling Japanese radios, clothing and cheap leather suitcases had sprung up on wooden carts parked along the sidewalk.

The biggest group of shoppers were PLO fighters, guns on their shoulders, shopping for consumer goods that are either prohibitively expensive or nonexistent in other Arab capitals.

"I'm not sure where I am going to be sent yet," said a bearded 21-year-old Palestinian fighter as he picked out a portable radio and tape stereo set. "But I might as well have some music with me wherever it is. I don't want anyone to say that we did not go out of here with music in our hearts as well as our ears."