What were the inaugural visits to foreign states by the last 10 U.S presidents during their first term in office, and who were the heads of states in those countries during those visits?
The last 10 U.S. presidents to visit foreign states during their first term in office were President Barack Obama (2009-2017), President George W. Bush (2001-2009), President Bill Clinton (1993-2001), President George H. W. Bush (1989-1993), President Ronald Reagan (1981-1989), President Jimmy Carter (1977-1981), President Gerald Ford (1974-1977), President Richard Nixon (1969-1974), President Lyndon Johnson (1963-1969), and President John F. Kennedy (1961-1963).

The heads of state in the countries visited during these first term presidential visits were as follows:

President Obama visited the United Kingdom (Prime Minister Gordon Brown), France (President Nicolas Sarkozy), Germany (Chancellor Angela Merkel), and India (Prime Minister Manmohan Singh).

President George W. Bush visited Mexico (President Vicente Fox), Canada (Prime Minister Jean Chretien), the United Kingdom (Prime Minister Tony Blair), Japan (Prime Minister Junichiro Koizumi), and Saudi Arabia (King Abdullah bin Abdulaziz).

President Bill Clinton visited Japan (Prime Minister Tomiichi Murayama), China (President Jiang Zemin), Mexico (President Ernesto Zedillo), Canada (Prime Minister Jean Chretien), and the United Kingdom (Prime Minister John Major).

President George H. W. Bush visited Japan (Prime Minister Toshiki Kaifu), China (President Yang Shangkun), and the United Kingdom (Prime Minister Margaret Thatcher).

President Reagan visited the United Kingdom (Prime Minister Margaret Thatcher), France (President Francois Mitterrand), West Germany (Chancellor Helmut Kohl), Canada (Prime Minister Pierre Trudeau), and Mexico (President Miguel de la Madrid).

President Jimmy Carter visited the United Kingdom (Prime Minister James Callaghan), France (President Valery Giscard d'Estaing), West Germany (Chancellor Helmut Schmidt), Poland (Chairman of the Presidium of the Supreme Soviet Henryk Jabłoński), and Mexico (President Jose Lopez Portillo).

President Gerald Ford visited Japan (Prime Minister Takeo Miki), West Germany (Chancellor Helmut Schmidt), and Mexico (President Luis Echeverria).

President Richard Nixon visited the United Kingdom (Prime Minister Edward Heath), France (President Georges Pompidou), West Germany (Chancellor Willy Brandt), Mexico (President Gustavo Diaz Ordaz), and Canada (Prime Minister Pierre)
What about Trump and Biden?
President Donald Trump's first foreign visit to a head of state was when he traveled to Saudi Arabia to meet with King Mohammed Bin Salman, which made him the first President ever to choose the middle east for this occasion.
President Joe Biden traveled to the United Kingdom for the 47th G7 summit. While there, he met with Queen Elizabeth II and Prime Minister Boris Johnson.