Secretary of State George P. Shultz said yesterday that Soviet leader Mikhail Gorbachev gave hints at the Geneva summit of greater Soviet willingness to negotiate the withdrawal of its forces from Afghanistan.

But Shultz added that it is too early to say whether it will be possible to find a political solution to the six-year-old Afghan war that has caused heavy casualties among the 115,000 Soviet troops engaged in an effort to quell stubborn resistance by Afghan guerrillas.

Shultz said Gorbachev "at least to my ear . . . had some interesting and a little bit different kinds of things to say."

He stressed that "I'd like to study it more carefully," and he reiterated the U.S. view that "the principal thing is addressing the problem of Soviet troops in Afghanistan and their withdrawal. It's the key."

The United States has backed U.N.-sponsored talks that have been trying to find a basis for a negotiated settlement involving Soviet withdrawal, setting up a neutralist government in Kabul and permitting the return home of thousands of Afghans who have fled into neighboring Pakistan.

Shultz, appearing on NBC's "Meet the Press," denied that the United States had made commitments to the Soviets before or during the summit that it would continue indefinitely to observe the provisions of the unratified 1979 strategic arms-limitation agreement known as SALT II.

Shultz said there has been no change from the policy enunciated by President Reagan last June. At that time, the president said the United States would continue to refrain from undercutting the treaty provisions but would reserve the right to change that policy if it decides that the Soviets are not complying with SALT II restraints or not bargaining in good faith at the Geneva arms-control talks.

SALT II is due to expire Dec. 31, and the Soviets had proposed that the two governments extend their voluntary compliance another year. However, Washington, which has accused Moscow of several violations, refused to make such a fixed commitment.

"The president has it under review, and if he makes a change, that will be announced," Shultz said.

There has been strong disagreement between Shultz, who favors continuing the no-undercut policy, and Defense Secretary Caspar W. Weinberger, who has advocated that it be abandoned. Reagan's national security affairs adviser, Robert C. McFarlane, has said that a decision is expected sometime in December.

Shultz also rejected the notion that the failure of the summit to produce substantive agreements on reducing nuclear weapons has put pressure on Reagan and Gorbachev to reach an arms-control accord when they meet here next year. At future summits, Shultz said, "We will have the same approach . . . that if there is an agreement to be found that is in the interest of the United States to make, we're quite ready to make it; and if there isn't, no amount of deadlining will cause the president to make one."

Shultz, without saying so explicitly, reinforced Reagan's remarks Saturday that the administration favors resumption of covert aid to Angola's UNITA insurgents, led by Jonas Savimbi, who have been fighting for years against the Marxist Angolan government supported by Cuba and the Soviet Union. Reagan made the remarks in an interview with editors and columnists.

Covert aid is a sensitive issue in Congress, which is considering legislation to permit overt assistance to Savimbi's forces. But Shultz answered "yes" when he was asked yesterday if the administration would ask Congress to vote against overt aid in Angola. The administration is known to believe that a covert aid program would be more effective in forcing the Angolan government to negotiate with UNITA.

"First of all, we support the freedom fighting of Jonas Savimbi and UNITA," he said. "Second, we want to support their efforts in a way that's effective. Third, we believe that if there can be a political solution, a negotiated solution to the problems of Angola . . . linked as it is to the difficulties in southern Africa generally, that's the way to go. And we're trying to do that."

A questioner asked what Gorbachev should think about Reagan's action, in the immediate aftermath of the summit, in advocating secret American help for insurgents battling a Soviet-backed regime. Shultz replied:

"He is supposed to think that the United States will support people who fight for freedom, and we will try to figure out how to support them in a way that will be effective. And I hope he has that message. And I'm sure he does."