"This is all new to me," offered Melvin Bradley, a newly appointed White House adviser on domestic policy, to M. Carl Holman, the president of the National Urban Coalition, and an old hand at breaking in presidential advisers. "I have to go to school and I want you to teach me," continued Bradley, a party in his honor quietly coming to life around him.

The schooling of Mel Bradley, 42, the highest ranking black member of Ronald Reagan's policy staff, took a turn away from the recent weeks' lunch and telephone seminars and into the living room of old-line Republican businessman T. M. Alexander. The informal buffet and reception was designed by Alexander and Howard Jenkins, the ranking Republican on the National Labor Relations Board, and his wife, Elaine, the president of One America, to help the younger man on the circuit expand his network.

Art Fletcher, an assistant secretary of labor for Richard Nixon, and the man Bradley called his mentor, advised him to organize quickly. "You can't anticipate the pace and implied power of the White House and the adjustment to protecting your turf. The pace of this administration is fast, this president looks like an activist. Mel has to get his act together in the beginning, there is no catching up in the White House."

Also offering advice were James Cheek, the president of Howard University; Lisle Carter, the president of the University of the District of Columbia; Dorothy Height, the president of the National Council of Negro Women; bank president Orlando Darden; Nan Johnson, executive director of the Links and attorney Timothy Jenkins.

"This is my sixth administration and each one has a different set of signals," said Howard Jenkins. "We have to give Bradley the opportunity to meet people of substance, build his power base and continue to be helpful to him."

During breaks in the politicking, the 60 guests munched on smoked turkey and wild rice, teased Alexander about his maroon velvet jacket and brocade tie, pulled aside Superior Court Judge William S. Thompson who heard Rep. Jon Hinson (R-Miss.) plead not guilty to a charge of sodomy yesterday, and sent messages home to recuperating attorney Sam Jackson, one of the elders who was missing, through his wife, Judy.

Bradley, who was wearing a three-piece gray suit with a red carnation, grew up in Texarkana, Tex., worked as a deputy sheriff in Los Angeles, as the assistant community affairs director on Reagan's gubernatorial staff, and at United Airlines as a marketing specialist, before he came to the campaign, the transition and now a $50,000 slot in the Office of Policy. He was one of the staff members who read Reagan's economic speech early yesterday and said, "I penciled in a few things. I think I won one."

Some of the reservations Bradley's well-wishers have about some of the pronouncements of the new administration were expressed far from his hearing range.

"We are trying to keep from prejudging," said Althea Simmons, the head of the NAACP's Washington bureau. "But we oppose tuition-tax credit, the sub-minimum wage and we are concerned that the budget cuts not be made on the backs on the poor."

J. Clay Smith, a Republican member of the Equal Employment Opportunities Commission, declined to discuss the transition team's negative report on the duties of the civil rights agency. On Bradley's role, he was pragmatic. "All of us Republicans, as well as black Democrats, have to give him information to be effective," said Smith.