They made a Closed Beta where people who signed up in the website could join at the begining of this month, but now I believe if you have Uplay and I believe it also shows up in your Steam Library, you can try an open beta up until the day 25!
https://thecrew-game.ubisoft.com/the-crew-2/en-us/beta/index.aspxEDIT: It's confirmed that you can actually level up this time unlike in the closed beta where you were locked in the rookie level!
