Slow network on APPS like Xbox & others

Hello i'm french so i'll try to do my best bc my english is not the best one !

I'm having some "network" problem, to be clear i just moved to windows 11 when i'm doing a speed test (ookla) i'm having my normal value ( ~1G) https://prnt.sc/LmaQmqGLBv0X when i was on windows 10 i had the same value 5 tests in a row. When i was downloading on steam or xbox app i was downloading at ~110 Mo/s but since i moved on w11 i can't reach more than 60Mo/s. I tired a few things and manipulation but nothing works... I would like to get my downloading speed back but i want to stay on w1.

I've seen some weird things if u like at this screen ( https://prnt.sc/cHJ_mq0MoXI2 ) 4 of my cores are at 95-100% and make my PC laggy at as u see download speed locked at 65Mo/s. ONLY ON STEAM FOR THE 95% PROCESSOR

Did anyone have any ideas to help me. Btw when i'm doing a direct download with my browser ( opera gx ) i'm having my normal speed of 100-110 Mo/s all this on w11.

I've tried so disable windows defender, fhusing dns, ... Nothing bring back my download speed on these apps ( seen the problem on Xbox, steam, epic games, didn't test the others )

Have a nice day everyone

:)