Windows 10 won't run after changing Maximum RAM

I messed up my PC and am desperate for help. After running msconfig and under the "Boot" tab going to "Advanced options", I checked the box next to "Maximum memory" thinking it would somehow allow me to use whole 8gb instead of 3gb of RAM... afterwards I clicked OK and it rebooted my PC. Since than I couldn't get it to run past loading screen, which would take around 15min. Then I left it for a while and it got stuck on a new loading screen with my account name and picture saying "Welcome". It took another 30 mins and it finally turned on my PC, taking forever to load my background icons and taskbar. Everything is extremely slow (10 mins for right click) and completely unusable.

Any idea?

Please help.

Thanks!

I didn't find the right solution from the Internet.

References www.techadvisor.co.uk/forum/windows-29/windows-10-wont-run-after-changing-maximum-ram-me-4651938/

Animated Explainer Videos