Lose all gears like a bad clutch

Hello, I am Danny.

When you say lose all gears do you mean it is hard to engage like grinding into gears? or hard to get into gear? Having a low fluid level would usually just make the transmission sound loud like having gears howl from lack of fluid. Manual transmissions have synchro gears that act as a buffer between the the gears to cushion shock when shifting. These synchros do wear and after time/mileage you will notice slop/play when engaging and also a noticeable grind when shifting. If your car is equipped with a hydraulic slave cylinder it could be worn/low on fluid as well. I have attached two tutorials for you to view. Hope this helps and thanks for using 2CarPros.
Danny-

https://www.2carpros.com/articles/clutch-symptoms

https://www.2carpros.com/articles/clutch-doesnt-work-sometimes-or-not-at-all