Thanks! That helps.

So I had never heard of this song before and my idea was that I could play the chords while they could sing it. So I went on Ultimate Guitar, and typed the song in and tried to play the chords while they sang. The song is below.

So maybe that is part of my problem, then?

Also, is it a good idea to make chord changes in the middle of a strumming pattern, or only when absolutely necessary. It's super easy for me to do that, but is it better to just do the last downstrum or upstrum (depending on the pattern) on the open strings and then switch at the end of a strumming pattern whenever possible?