Key: " this started happening after I opened geforce experience and it installed something im not sure what but it slowed my computer down immensely"
I recommend a closer look using both tools and be sure to sort data presentation via the column headers. And you may need to wait a bit - some background process starting up and causing the slowdowns. May not immediately happen.
If Task Manager and Resource Monitor are not revealing any bottlenecks then take a look at things via Performance Monitor.
In any case, uninstall GeForce experience. Download again and reinstall while carefully watching for any extra "somethings" that you can uncheck and avoid their installation.
Task Manager lists the applications etc. being launched at startup. You should be able to identify everything therein. If something is not identifiable then research accordingly. Find that "something".
Cumbersome and difficult to use but still, with some digging, identify a problem