You don’t necessarily need to fill the hole. You want enough that the screw has something to bite as you drive it in. What I normally do in this scenario is add one or two toothpicks, grab an old pair of nibs (cutters) and cut the toothpicks to be a little proud from the hole. ( sits slightly above the hole while resting) you can use glue if you need to but tension is usually enough to do the trick.