Glue: Elmer's White Glue will work just fine. Some folks use CA or "super glue". Testor's makes a wood glue.
Sandpaper: I use 220 grit for heavy sanding, such as leading edges of the wing. Most everything else 320 grit or 400 will do. Any brand.
A
sanding block is helpful. I've seen simple ones such as wrapping a piece of sandpaper around one of those Testor's square paint bottles.
You didn't ask, but...
building board: you can use a cork bulletin board, some guys use a commercial grade ceiling tile from local home improvement stores.
Use the search feature on this forum, most likely any question you have there is a thread that explains it, and sometimes with pictures
. Of course, anybody on this forum will be happy to answer any questions you post.
Since you can't build, yet because of your injury. Read the plans front and back and all over. Get a good idea in your head of what's going on before you start.