Yes it has a drainage hole.
That's good. If the soil stayed wet very long, repotting it was a good idea.
I'm asking because I'm a young person trying to learn about bonsais and how to take care of them. I have had this one for a few years and I'm trying to raise it into a nice bonsai
You are going to need growth. I think this plant is still a bit too young and the trunk a bit too thin. So, your first concern is to get it healthy. As you already repotted it, I think now you need to wait and see how it responds (which you already suggested, so I agree with that).