i have almost everything ready to play, but the issue is that the game doesnt let me steer, the game doesnt detects the L3 for steering, i have to use the Keyboard controls for it but when i use it like that is really hard to handle the car because at the little movement with the L3 the damn pilot steers a lot

Hi, welcome to LFS and the forum!

The L3 is a button, right? Normally when you use a gamepad, you use an axis (steer/joystick) for steering. I'd use 1 of the joysticks for steering.

When players use keyboard they use the assistance, because a binary control like a key (or L3) makes 'the damn pilot steer a lot' indeed. But i don't know if the keyboard steering assistance works with a your controller.
Have a look at this; https://en.lfsmanual.net/wiki/Options#Controls

You could also tweak the maximum lock (steering angle) in your setup, but that might not give you the desired result. More about that on https://en.lfsmanual.net/wiki/Basic_Setup_Guide#Steering

The L3 is a analogic control, like the android gamepads for shooter games but in a physical form, well, i tried with the keyboard steering assistance and it worked pretty well, is not that precise like i wanted but i did 3 laps with the configuration with almost no issues, i will have to play like that, thanks for the help tho.

You can use wheel turn compensation that will make your steering non-linear. But much better is just to lower the max lock on a given car, which will give you much more precision on the analog stick axis for steering. One example, in XFG on BL1 I could drive normally even with 12deg (out of 30deg) max lock.