You knowledge on the subject is pretty limited and it is quite clearly expressed in your response.

1. They didn't tell people to not wear masks, then change their minds. That is revisionist or simply ignorant. They specifically told people to reserve N95 and surgical masks for people on the front lines because there was a massive shortage. The science behind why masks are needed and work was well established and further verified with this pandemic by further studies as well as data analysis.

2. What Biden did with vaccine rollout was not a 'continuation of Trump'. This is , yet again, either revisionist or ignorant. Trump did not have a plan to actually get shots in the arms of actual people. He also purposefully obstructed the incoming administration by denying them information and resources. Biden, even before taking office, was working with state governments and private entities to actually get shots in people's arms. The Trump plan ended at dumping vaccines off with the states and had no further guidance, direction, cohesion, or leadership beyond that point. Furthermore, he literally undermined vaccine adoption by conservatives with his own words and behavior, political reasons. Meanwhile, he quietly went and got vaccinated himself.4

3. Regarding the school situation. It was important to keep kids out of school initially as we learned more about the virus. The logic behind it is easy to understand even for those poorly versed in how viruses spread. Allowing onsite schooling, masked up, would have been the 'right' call however, nobody had a crystal ball and nobody knew exactly how the virus worked at the time.

Really though, even taking into account your revisionism and/or ignorance it absolutely should be expected that there will be back and forth, changes in best practice, adaptation of different precautions, and so forth as we learned more about a *new* virus. Like duh, seriously-fucking-duh.