Where and how can one find and identify righteous companionship, especially if one is not skilled at socializing with people?

The best place to find good companionship is in the mosques, as they are the houses of Allah and the purest places. So, if you see someone who is keen on performing congregational prayers there, and you perceive goodness and righteousness in them, then approach them and get to know them. And once their uprightness and good character become apparent to you, hold fast to their companionship.