Can someone tell me how to move a background

You can't move a backdrop (stage equivalent of costume) but you can use a sprite as a background and move that. Just make sure it is behind all the other sprites.

like

play drum ( v) for (0.2) beats

THX!

You need a variable Xscroll and then change Xscroll by +/- amount depending on what key you push and then have a Forever Set X to Xscroll, and then for other sprites with with Set X to Xscroll +/- WidthOfXscrollScreen * 1/2/3/4/5 etc depending on when you want it to appear.

Sigton