President Reagan filled the top spots yesterday at the Office of Personal Management and the Peace Corps and three sub-Cabinet spots in the Department of Health and Human Services.

Nominated to run OPM was Donald J. Devine, a University of Maryland professor who headed the OPM transition team and was a regional political director for the Reagan-Bush Committee. Loret M. Ruppe, who was cochairman of the Reagan-Bush Committee in Michigan after being the chairman of George Bush's campaign there, will be the Peace Corps director.

At HHS, Reagan nominated Dr. Edward N. Brandt Jr., vice chancellor for health affairs at the University of Texas, as assistant secretary for health and said the position would be elevated to undersecretary of health "with a reorganization plan that will be announced later."

The reorganization plan apparently will give the department several undersecretary spots -- one for all the health programs, to be held by Brandt, another for all the income maintenance programs, to which David B. Swoap, former California welfare director, already has been named, and possibly others with responsibilities divided according to subject area. Over all this is likely to be a deputy HHS secretary, which would give HHS an organization roughly akin to that at the State Department, which has a secretary, a deputy secretary and a wealth of assistant secretaries with no responsiblities divided according to georgraphy.

Brandt's deputy will be Dr. C. Everett Koop, now surgeon-in-chief at Children's Hospital of Philadelphia and professor of pediatric surgery at Univerity of Pennsylvania Medical School, who this week resigned from the boards of several antiabortion groups to take the HHS job. Koop says he has been active in the antiabortion movement for five or six years.

Carolyne K. Davis of the University of Michigan, where she served as dean of the nursing school and is now an associate vice president for academic affairs, will head the Health Care Financing Administration at HHS.

The field is narrowing for some top jobs at the Justice Department. Frontrunner to head the criminal division is D. Lowell Jensen, the district attorney for Alameda County, Calif., and a personal friend of White House chief of staff Edwin Meese III. And the lead candidate for associate attorney general (the No. 3 position at Justice) is Rudy Guiliani, a New York lawyer who was an assistant U.S. attorney for the Southern District of New York for eight years and associate deputy attorney general in the criminal division from 1975 to 1977.

Rumored to be on the list of candidates to head the civil rights division, meanwhile, are Equal Employment Opportunity Commission member J. Clay Smith and K. William O'Connor, chief of staff at the Justice Department's inspector general's office.

Barely a month into the new administration, Sen. Edward M. Kennedy (D-Mass.) and former vice president Walter Mondale are getting a head start on the 1984 presidential campaigns by forming political committees.

Kennedy plans to put a fund-raising committee on the record at the Federal Election Commission next week, according to a Kennedy aide, and Mondale set his up last week.

The committees will give the two potential presidential candidates a fund-raising base for 1984, similar to the Citizens for the Republic committee that Reagan put together after losing the GOP nomination in 1976. The committee kept his campaign organization intact and active for four years.

Kennedy's group will be called the Fund for a Democratic Majority, Mondale's the Committee for America's Future.