How To Select Vertices

So I am a huge Blender newbie and had a very basic question. I’m importing models from a posing studio to edit in Blender, but when I switch to Edit mode and attempt to delete vertices I’m stuck on selecting bones instead of vertices, edges, and faces. I was able to successfully switch to editing vertices once, but I don’t know how I did it. I’m wondering if there’s a hotkey or easy way to switch to selecting and editing vertices rather than bones?

I included a picture of the bone select mode that I seem to be stuck in.

I apologize for the newbie question. Thanks in advance for any and all help!