The Washington National’s Opening Day is this week (April 1st), and Biden will not be throwing the first pitch. It is customary for Presidents to throw the first pitch on Opening Days and/or World Series.
When asked if Biden would throwing the first pitch, White House Communications Manager Jen Psaki said, “I know the President’s eager to get out to Nationals’ stadium. Many beautiful days, many beautiful baseball games ahead this spring. It’s not on the President’s schedule this week but I certainly expect that baseball fans will be hearing from him in next couple of days.”
To be fair, Trump declined to throw the first pitch in 2017, saying it was due to a scheduling conflict.