Hello im new in lfs and im playing on xbox controller and i have a problem with the in game wheel i mean the car cant go straight and its shaking how can i fix this?

Maybe set up a small dead zone in the LFS settings.

No need to do anything special with controller settings, just reduce the max lock under steering tab in car setup in the garage and you are good to go. Set wheel turn compensation in options/controls to 0.

For XFG in BL1 you can use as little as 12deg max lock (30 is the default), but you can find something small enough to give you precision and at the same time big enough that you can still do tight turns or exit pit.