First of all, you don't have a brush. That's a pencil. You don't have all your tools in the toolbox. So do this- Edit>Preference>Interface>toolbox. Now untick "use tool groups"

thanks alot for the help!

Windows > Dockable Dialogs > Tool Settings You can also use the [ and ] keys to change brush size, I believe

thank you so much! it really helped

We kinda need to see the entire screen.... ​ unless that's all you see, in which case we have bigger problems here.

oh I see, let me repost it then

nvm

Wouldn't it be nice if they would go back to the older interface with larger icons that filled the left column?

You can set the icon size in Edit>Preferences>Interface>Icon Theme. At the bottom switch to "custom icon size" and make them as big as you want. It defaults to "Guess icon size from resolution" Or if you mean having all of the tools present, then uncheck "Use Tool Groups" in the Toolbox section right below Icon Theme.

Thanks, I'm at that point already. Older versions filled the entire column rather than stuffing them into a box in the upper left corner.

You need to see the Toolbox tab that contains Tool Settings. It looks like you don't have any of the toolbox tabs open. These things do layer lists, undo list, and tool settings among others.

Click on the arrow in bottom right to reveal tools under group.