President Reagan warmly welcomed West German Chancellor Helmut Schmidt to Washington yesterday as both leaders appeared determined to put relations between themselves and their countries on a firmer footing than that of the often stormy days of the Carter administration.

"Make yourself at home," Reagan told Schmidt during a full-dress military welcoming ceremony on the South Lawn of the White House under warm, sunny skies.

In their public remarks at the start of Schmidt's two-day official visit, both leaders said things the other likes to hear.

Schmidt spoke of the "excessive Soviet arms buildup" and the "challenge toward the community of nations resulting from the continuing Soviet intervention in Afghanistan," assessments meant to bolster U.S. confidence that Bonn remains firm in its commitments to western defense.

Reagan promised that the United States will work toward meaningful negotiations with Moscow to limit European-based nuclear armaments. That is very important to Schmidt at home where he has come under sharp attach from his own party's left wing for compliance with a NATO plan to base new U.S.-built missiles in West Germany.

Reagan thanked Schmidt for support during the Iran crisis and added that "our economic policies should be as closely allied as our defense policies." A major point Schmidt is trying to make during this visit is that extremely high U.S. interest rates are having a serious impact on European economies.

Later in the day, Arthur Burns, former chairman of the Federal Reserve Board and Reagan's nominee to become ambassador to Bonn, also stressed the theme that good political relations betweent the two NATO allies were more important than ever before.

After a lunch with Schmidt and Secretary of State Alexander M. Haig Jr., Burns spoke of "a certain element of restlessness in Europe" and said that while economic and political ties betweent eh two countries had always been strong, they now "must become stronger still in the interest of protecting the future of the western world."

Schmidt and Reagan met for 70 minutes in the Oval Office and will meet again today. Officials close to the discussions said the meeting's dominant feature was that both leaders apperaed determined to get along and to work on developing personal rapport.

Although Schmidt has a crucial interest in the arms talks and interest rate issue, officials said Bonn did not pass demands on the White House.

By the same tokeln, despite the encouraging public words, there ws no indication that the administration is prepared to take any specific new steps toward meeting voluntarily some of the German concerns.

On the interest rates, which are causing money to flow out of Germany and contribute to European recession, administration officials briefing reporters said Reagan expressed the view that, when his economic program is implemented, interest rates and inflation will decrease.

Other officieals close to the talks said Reagan pointed to the declining price of gold as a sign that interst rates also may drop. But he reportedly made clear that he would stick to the tight money policy because token measures will not do and that the situation would be far worse if the stronger medicine is not taken.

On starting negotiations with Moscow on European missiles, officials said the United States is staying with Haig's recent declaration to NATO that talks will start by the end of the year. They said the specific date would be determined after Haig meets Soviet Foreign Minister Andrei Gromyko in New York in September.

Reagan and dSchmidt also discussed the possible future makeup of the French government under newly-elected socialist leader Francois Mitterrand. Allied leaders are concerned that communist officials may be appointed to the French government hierarchy.

Later in the day, Schmidt met with Defense Secretary Caspar W. Weinberger and then with a group of leaders of American-Jewish organizations. A spokesman for the Jewish group said that while they still had some concerns about German policy toward the Middle East, they were satisfied with their talks and that Schmidt had assured them there was no change in Bonn's special commitment to and relationship with Israel.