Hi Reilly515,
It seems you're in Split View and need to exit. We're here to help you with using your Mac.
Try these steps:
Exit Split View
- "Move the pointer to the top of the screen to reveal the window buttons.
- Click the full-screen button in either window. That window exits Split View.
- The other window switches to full-screen view. You can switch to the full-screen window with Mission Control, or use a Multi-Touch gesture such as swiping left or right with four fingers on your trackpad."
Use two Mac apps side by side in Split View
As stated above you can also cancel Split View with Mission Control.
Press the Mission Control key on your Apple keyboard or Touch Bar.
Learn more here:
Use Mission Control on your Mac
Let us know if that helps.