With PRIME render offload you have to tell the software which GPU to run on, and the easiest way to do that is with the prime-run wrapper (part of the nvidia-prime package). For example:
prime-run glxinfo
You can add this to your Steam game's "Launch Options":
I tried what you told me and i still got the video laggy situation, with one exception, the mouse was not laggy for one or two seconds, but good news i got more data
I tried adding the following to the steam.desktop
That’s not what I suggested at all. Steam games have a “Launch Options” box so this can be applied per-game, and while you can add it to the desktop launcher what you’ve added there is incorrect syntax.