Depends on circumstances a lot. It’s easy if you’re in college/work with similar people. Otherwise it might be hard to start, especially if you don’t have a lot of free time.

I moved a lot alone and had to make a new social life a lot. during school, for high school, for college, then jobs, then moved country. Except for last one where I knew a few people every other case I had 0 friends carried over. Hardest to have a social life was during the time I was working on jobs as the ability to meet new people decreased a lot.

So basically it is hard when you don’t goto college and job where you are forced to spend time with people, but that can also sometimes makes it hard to hangout with the same people outside of work.

So far things that have worked out for me:

• People with same interest that you randomly meet sometimes.
• keep your social media connected and when you see stories of people doing things you like strike a conversation about it. Don’t force to have full convo, just say your piece about that story and leave it be if it doesn’t go any farther. Small talks just sharing some sentences are good starting points. If it happens a few time with same person you might find someone you have common things with.
• try some group activities that doesn’t have to have a lot of talking. Something you can be present there just doing your thing, it could be local recreational sports group, volunteering, library, etc.
• friends of friends, statistically your friends in average have more friends than you, so just hangout with them in group activities, and try to make new connections. You have to start somewhere.
• online friends, sometimes it just helps to have people to talk to, careful on who you’re hanging out with, but fandoms and such online are good to make friends that you can talk to without responsibilities of maintaining a relationship. It’ll help you be more open on sharing your interests.