You get most of the games, but not all. To get every Sabres game outside of the Sabres home market you need ESPN+, a basic cable or streaming subscription that has ESPN and TNT, and the NHL Network which probably available as an add-on to the cable/streaming service.
If you only have ESPN+ you get probably 60-70 games per year.
Also if you have Hulu and/or Disney+ already, there is a bundle you can buy that has those two plus ESPN+ which is a pretty good deal.