Destiny 2 will become unavailable on Battle.Net, the first of October, so you need to complete these first, if you want to keep playing.
“With Bungie and Activision’s split earlier this year, the studio is migrating Destiny 2 on PC from Battle.net to Steam. If you’re a PC player, you need to set up an account migration ahead of Shadowkeep’s release on Oct. 1″
First, you will need to go to Bungie’s website, they set up a page where you can directly start the transfer here.
After clicking “transfer”, you’ll have to login to your Battle.net account.
Once you’re login successfully, your characters, Destiny 2 Licenses and Silver will be display if you did it right.
Then you need to repeat the process with Steam, Bungie’s website will take you to the Steam login page, login and accept the terms anc conditions.
Once you’re on Steam, you will have a similiar page with your licenses, characters…Keep going foward until it says “success” Once you see the check mark and all the details correct, you’re done, and you just have to wait for the first of October.