I set up a server, and after playing for a bit, realized that I couldn't make any stone tools... None of the other 3 people that were playing could make stone tools either, so i tried to google why that might be. Around that time one of my friends left and went into creative and found that they had no tools in that menu either. If this isn't a bug, then there needs to be somewhere that explains how to fix this...
In the picture, the pickaxe I have was obtained using commands.