You are talking to us here, now. I know you do rock climbing and weight lifting. If you have friends, you talk to them too. It’s not different from that. You are doing it already. There’s not a formula.
What friends can do is tell their friends you are a great guy and introduce you to other people. That’s what networking is, the same way you network computers, you network human relationships, by connecting them.
Ha ha ha ha, no. We do have savings so at least some cushion but I took years off when my kids were born, got a late start in college, started a career later, I would say I got the time when I needed it I guess. But not likely to have enough to take time off paid work again at the end.
Most people don’t get to decide, they get disabled or laid off & cannot find work and are forced into retirement. I’m in good shape and work in an office so probably can keep going as long as jobs last for me, and our life will be better if we keep working.