Start with some of the easier to get into semi-private trackers such as MAM (books / audiobooks) and TorrentLeech (general) to build up some history. I can send you an invite to TL if ya need one just DM me.

You could also study the rules and join RED (music) but their wait times to actually interview are ridiculous. Its much easier to get into Orpheus which shares a lot of the same users, who are happy to upload on both.

Some of these have forums that you can use to get access to invites to more exclusive trackers.

I got into TorrentLeech and MAM with the intention of building reputation and getting into a better tracker, but frankly I've never needed to take that extra step. If I can't find something on TL I can make a request and someone will have it uploading within a day or two, but I've only ever had to do that with obscure stuff like Pros vs Joes

There are pretty okay trackers asking for no proofs on open signups. It's mostly a matter of patience. You can even just sign up for everything and see what's a good fit, but be sure to use unique passwords on everything to be safe.

If FNP or LST open up again I would suggest signing up, they are shaping up to be good entry level trackers. Also TL usually opens a couple times a year. It's a massive site but kind of a mess when it comes to curation. Don't use iPT unless you have no other option.

People will tell you to join book/music trackers to rank up, but unless you like grinding I'm not sure this is the best route.

Red -> upload to get invite forum -> access everywhere else

Start with TL and MAM and work your way up there. MAM has an invites section for example, you can get into lots of other good trackers like Aither, PixelCove, OPS, ANT/NBL, BBT, etc if you meet the invite requirements listed in each of the invite threads.

Not to highjack the thread but is it required not to use a VPN to join private trackers? I'm in a similar situation as OP and want to up my speeds, but I'm worried about privacy