LOD: suggestions for a noob

Good day
I am making a race game where the player car mesh is particuarly complex.
In the home page this mesh must be completey visible, but during the race the player car is really very small and for sake of performance I created a smaller mesh just for the race, with fewer materials and textures.
I would like to understand if Unity has an automatic management of mesh / texture LODs, and so the work of creating a second mesh for the play stage is useless because it is some how automatically managed, or if my approach is actually the correct one.

Thank you in advance.

LOD documentation.