First define your problems ;)

If you want to get into management and deal with those kinds of people problems, then there are lots of management training courses around. An MBA is at the upper end of that range.

If you're having problems fitting into teams and getting along with people (actually quite common in dev teams), then maybe look at therapy or personal coaching. I spent a few years in therapy and it really helped.

If it's office politics and the like - some workplaces are toxic. I can't deal with those even with the training and experience. Life's too short to deal with that bullshit ;)

Depends on what you mean by "people problems".

Perhaps read some books on negotiation if you have issues getting others to see your point of view.

Nervous about speaking in front of a group? Try Toastmasters once the world opens back up, or hire a coach.

Books are a good first resource once you identify the areas in which you want to grow.

You can also try therapy.

Totally agree with this. Knowing how to handle your own emotions is a key "people skill". And therapy really does help with this.