I am teaching an online class that uses Blender. Sometimes a student will turn in an assignment and it opens showing different menu choices. I'm not sure how it is happening and how to get back to the default menu choices.
The menus adapt to changes the student has made, such as enabling an add-on; turning overlays on and off; creating or renaming a workspace. There are a few things you can do.
If you really want to set everything back to the default, go to the File menu, select Defaults->Load Factory Settings:
Your example of Layout versus 3D View Full is probably because you and the student are using different releases of Blender. You can partially alleviate this problem when you open the student's blend file. Open it by using the File menu "Open" item. In the dialog box, there is a hidden panel that you can open with the 'n' key:
If you disable "Load UI" then you will get the interface that your used to, rather than the student's layout.
The second item you point out is an overlay. You can change overlays in the overlay menu:
You will see different overlays depending on what editor you are in and what mode the editor is in.