im having a hard time understanding if the link code is for people who are new to PSO2 or do the already existing players link to steam i don't get it well anyway a good reply or answer will help and thanks for the help

The link code is for existing players who want to use the same PSO2 account on both the MS Store/XBox version and Steam version (you get the link code from whichever version you used initially to create your account).

If you are a new player, you don't need a link code since there is nothing to link.

New players don't need link codes, unless in the future they plan on playing on the other platform like goin from PC Steam -> Xbox.

Never know when you might wanna sit back on the couch and play PSO2 on the TV.

one unintended bonus of the linkcode is it allows players to double-up on the nice sonic collab bundle on both steam / windows plats, on the same PSO2 account.