Attorney General-designate Griffin Bell said yesterday that he favors assigning pupils to neighborhood schools and believes that busing should used to achieve school desegregation only as "last resort,"

"We're going to try to improve the educational process, while at the same time according everyone their constitutional rights," Bell told reporters during a brief meeting at the Justice Department.

His nomination has come under fire from black groups that dislike some of his decisions in civil rights cases during his 15 years as a federal appeal judge.

This opposition has made Bell perhaps the most controversial of President-elect Jimmy Carter's cabinet choices. In an effort to defuse the criticism, Bell has told black leaders that he will name a black as either deputy attorney general or solicitor general, the Justice Department's second and third-ranking jobs.

Yesterday he said that he has "someone in mind" for solicitor general and, although he refused to divulge the name, his remarks left the impression that it is Wade H. McCree, 56, a black and a judge of the sixth U.S. Circuit Court of Appeals.

Bell conceded that McCree was on his list for solicitor general. But he added that, since McCree is an active judge, it would be inappropriate at this time to discuss whether he will leave the federal bench to join the Justice Department.

[In Detroit, McCree said he had been contacted about both jobs by Carter's office and would accept if one is offered, Associated Press reported.]

Bell said he also had given considerable though to the deputy attorney general appointment but had not yet made any decision. As to other key posts such as director of the FBI, he said: "I haven't gotten that far yet. I've only focused on the deputy attorney general and solicitor general so far."

In any case, Bell said, he does not to plan to announce his choices fro subordinate posts until he is confirmed as Attorney General Sources on the Senate Judiciary Committee said yesterday confirmation hearings probably will begin next week.

They said the date probably will be fixed this week when Bell meets with the committee chairman, Sen. James Eastland (D-Miss) and other committee members. Bell is in Washington for four days of courtesy calls on congressional leaders and briefings at the Justice Department.

In his meeting with reporters, Bell said he had only just started the briefing process and thus was not yet sufficiently as possible Justice Department investigations into abouse of power by the FBI and the Central Intelligence Agency.

The one policy area where he didi answer questions in some detail was school desegregation. On that subject, he outlined a point of view that sounded basically in accord with his own past statements, with those made by Carter during the presidential campaign, and with the present policies of the Justice Department.

Bell noted that the Supreme Court has endorsed busing as a remedy for school segregation by deliberate official acts, such as pupil assignment or the drawing of school-district boundaries. In such cases, he said, the Justice Department will continue to press for busing as a corrective.

Under outgoing Attorney General Edward H. Levi, the department generally has opposed busing as a remedy in cases of so-called de facto segregation - those created by racial population concentrations. Last summer the department, at President Ford's order even drew up proposed legislation that would limit busing to situations of officially created segregation.

Although Bell said nothing about legislation, the thrust of his remarks indicated that he agreed with the general outlines of this approach.

He noted that busing "doesn't amount to much of a problem in small, rural school districts, where children always have been bused and where it's simply a question of reconstituting the bus routes."

The big problem, he said, occurs in cities. He added: "I think it upsets most Americans to take children away from their neighborhoods."

Bell observed several times that there would be situations where other measures would prove unworkable and where, as a last resort, busing might be required.

But, he said, "I think neighborhood schools are preferable, all things being equal. And I that almost all other Americans think the same way."