Collision with obj files

ive recently ben working on an open world game however i do not no how to create the colision eith an obj file(which is the land you walk on).my character just falls through and i cant do anything to change you have any ideas?

Hi @anakin_Skywalker! Your land object need an (static) rigidbody component and a (box) collision component. Make sure you give the collision component the correct half extents.

i dont really know what that means as im new to it so is there any dumbed down version of it?

Can you share a project to show the issue you are having please?