Can I change the order of the songs?

Assuming you are on iPhone, open the music app and open your playlist. In the top right corner, there is a button with three dots. Tap it

Then tap edit.

Now, next to every song is a red circle to the left and three lines to the right. Press and hold the three lines, and drag your finger up and down to change the order of the songs.

When you finish, tap done.