Is it better for a basketball player with torn ligaments in foot to get surgery or let heal naturally?

Depends where: In the foot, the lisfranc ligament (middle of the arch) is a notorious subtle injury that usually requires surgery and without it, function, stability and ability to return to sport is often impossible. If it's the plantar fascia, let it heal naturally as it is below standard of care to "repair" that ligament surgically. Where is the ligament tear?

Torn ligaments: That is hugely dependant on what is torn , how badly it/they are torn , where the ligaments are that are torn , etc. See your team physician/podiatrist for the help you need. They are there for you - good luck !