There are around 5-6,000 different crypto currencies (compared to just 160 national currencies), with a total valuation of around $3 Trillion. Too many to even list..
Bitcoin represents around 40-45% of that value, ETH another 15-20%.. The top 10 (incl. stablecoins) are 80%, the top 100, over 96%...
Most popular exchanges are limited to a selection of perhaps 100 different coins, so unless you have loads of accounts you will have a fairly limited choice of crypto available to you.
Any of the top 10-20 could easily increase 2-3x from here over the next few years, but unlikely to do much better. If you want BIG gains you need to look further down the pecking order...and then find an exchange that lists the ones you want.
I look for coins that are newly listed on popular exchanges. Look for coins that have a high turnover. Eg. BTC daily volume is typically less than 1% of its total valuation; most are 1-5%, but some may be over 50%. High volume tends to correlate with a rising price as more people are jumping on board (but not always, so beware)..
Next look at the potential value or the number of unissued coins.. around 90% of all possible BTC (out of 21 million) is already in existence.. so there is not much more inflation of its supply possible. At the other extreme, Shiba Inu has only 50%.. out of a possible 1 quadrillion coins.. and it's already in 11% place with 1% of the total crypto value.. it might increase a little more, but it won't continue its recent past performance..
If you're willing to watch continuously there are some coins that can jump 20-30% up and down every day (sometimes a few times every day). Even if the overall trend is down, you can often make 15-20% every day by timing the swings. IOTX is one that I've been playing with over the past few weeks.. My 1st (small) buy was up 7x, although it's since dropped back, but daily swings are still typically 20-30%, so plenty of opportunities to profit. It's currently in 64th place, with $2.5Bn total valuation, and around 15-20% daily volume/valuation... and there are only 5% of the coins left to be issued... so it ticks all my boxes.
But for these more volatile coins only "invest" what you are prepared to loose.
Good luck, and have fun..