When it comes to Facebook, Instagram, and other mainstream social media, just stay away, it's not worth it. I had Facebook, and it was just full of trash. I haven't had Instagram, but it's not very appealing either.
A LinkedIn account, however, for professional reasons is very much advised. Or Glassdoor.
Although over the recent years I saw some decline in quality on LinkedIn, as it's getting full of shit posts, but you can completely disregard what's on the feed. What you need LinkedIn for, is to build a professional profile, have your former and current coworkers in your network, and find and apply for jobs. Or even just let opportunities come to your inbox once you have an impressive profile.
The most amazing workplace I've ever had was possible thanks to LinkedIn, with almost no effort on my part. I have to say, this isn't typical though. It's only likely happening in countries where there's a labour shortage. But a recruiter (among tons of others) found me from a well known company, their opening looked good to me, so I gave it a try. After just one interview I was hired, and I didn't even have to apply for the job.
My most recent job was with a relocation to a different country. I can't even imagine how this would've been possible without LinkedIn or Glassdoor. But I achieved one of my big life goals.
A career advice I got about ten years ago: create a LinkedIn profile and always keep updating it. If you do so, you'll see it's kinda awkward to go back in time and retrospectively edit things and connect with former coworkers. But since you haven't had an account yet, I don't see any other choice for you.
As for Glassdoor, it's maybe a bit less popular than LinkedIn, but nowadays you can find opportunities there too. The best strength of Glassdoor is that you can find reviews of companies, sometimes they're also reporting their salaries so you know what to expect. In some cases, individual reviews may be misleading as they're forced by the company (which is btw against the terms of use), it can be a good indicator if you find thousands of good reviews or thousands of bad reviews.
Regarding the fediverse (Mastodon, Lemmy, Pixelfed, PeerTube, etc.), they're much better than their corporate equivalents in terms of quality, but they're not immune to misinformation either. And also not immune to the user's own stupidity. Obviously, don't share what doesn't belong there.
Edit: added notes for Glassdoor
Wait, the keyboard layout standardization has been done by Microsoft?!