Trump speaking about the withdrawal of troops from Afghanistan one month ago:
I started the process, all the troops are coming home, they couldn’t stop the process. 21 years is enough. They couldn’t stop the process, they wanted to but couldn’t stop the process.
And in April:
I (Trump) made early withdraw possible by already pulling much of our billions of dollars and equipment out and, more importantly, reducing our military presence to less than 2,000 troops from the 16,000 level that was there... Getting out of Afghanistan is a wonderful and positive thing to do... I planned to withdraw on May 1st, and we should keep as close to that schedule as possible.
Whether the US should have withdrawn the rest of our troops or whether we should have done so differently is debatable, but to be clear, Biden finished the last part of what Trump began. He just did it three months later than Trump said he would do it.