Playing through all of the campaign missions in Battlefield 6 isn't something you're likely to do more than once. Many might have seen this game as a CoD killer, but sadly, its campaign is really not that special and basically amounts to a very average AAA FPS campaign, i.e. the kind of thing you play once before jumping into multiplayer forever.
There are campaign rewards you can earn for completing the missions and collecting the dog tags hidden in each, but beyond that, it's up to you how you play and what difficulty you decide to play through on. You can see all campaign challenges at the bottom of the challenges tab on the start menu.
