Drag and Drop tools not working

Hi. I'm very new to Adobe Animate. I try to use the pencil tool but it's not in my tool bar.
I noticed that by pressing three dots in the tool bar it opens a selection of tools I can drag and drop to my tool bar. There's the pencil tool there but no matter what I do I can't drag and drop it or any other tools to my tool bar. This is very annoying. What should I do?