Life for your teen will probably be much easier if they have at least 1 or 2 people that they trust and hang out with.

Some teens have no problem making friends, and don't
really require any assistance.

However, some teens are loners, introverts, and/or
self-conscious about “something”. And they may
benefit from some encouragement/assistance from you.

Perhaps, helping your teen to identify a group
teens/classmates with similar, positive interests.

A place to start… more than likely, your teen’s high
school has a number of school-sanctioned
clubs/groups/activities that provide this opportunity.

In addition, there are opportunities outside of school for your teen to broaden their social skills: church-related, volunteer-related, work-related, etc.