Can someone please tell me why I have a browser on my mobile Metamask app but only a wallet on my desktop app
The Metamask app for Desktop Computers is an extension to certain browsers (chrome, firefox & brave for now), meaning that you can’t use is without one of those browsers.
Here are some videos that can help you to understand even better how to use the MetaMask wallet in it’s desktop app.
- How To Use MetaMask: Ethereum Wallet in your Browser
- Crypto Beginner Series - Metamask Tutorial - Ethereum ERC 20 Wallet
- Metamask Tutorial
Hope this gives you a clear view of the subject, keep learning! 
If you have any doubt, please let us know so we can help you!
Carlos Z.