Bear in mind what you're about to read is the ramblings of an autistic women. I may be a woman, but the world still looks a lot different through my eyes than it does to other women, so take what I say with a grain of salt.

Anyway, definitely not too late to date. That part's simple to answer.

As far as losing weight, depends really on how much you weigh as for how it'll effect your dating options. For men, I think gaining a little muscle is more important than losing fat. Even if you weigh quite a lot, if you've got a bit of muscle showing through there will be women who find you attractive. I can't speak for all women, but to me, it's more attractive when a guy's body shows that they're thinking about their health than it is when a guy has a traditionally attractive physique. In other words, a little muscle shows you're putting work in regardless of if you're successfully losing much fat. You'll probably inevitably lose some fat anyway if you gain some muscle, because it speeds up your metabolism.
In the end though, physical appearance isn't as often important to women as it is to men. If you've got a personality that meshes well with somebody, they'll probably like you anyway.

What you're doing to meet people is good, but another good way to find people Imo, is through your hobbies. Although that can be tougher if all your hobbies are male dominated. Even if you do meet women into it in that case, I speak from experience when I say we're expecting to be approached and tend to already have our rejection locked and loaded. If that's the case, I'd say the best option is to wait and see if they show interest in you first.

Making more friends is also good. Besides the fact that it's good for your mental health, they can also introduce you to people, and somebody who knows you well is gonna be way better at finding people who will match well with you than anything like dating apps or searching aimlessly. I was introduced to my wife by a friend. They didn't even intend it as a romantic setup, they just thought we had a lot in common and would make good friends. The romance happened to blossom from that.

I'd end this off by telling you it's good to learn to be happy being single, but I know that's harder than it sounds, and sometimes you can't manage it until you've already been in and out of a serious relationship or two. Do take care of your mental health though. A happy man is an attractive man.