You’re not missing anything content-wise if you play it solo. In solo mode you control all 4 of your party members during their turns, and in the multiplayer mode you control some of your party and your friend(s) control the others. The game content is the same but the experience is very different since multiple players are generally less tactically coordinated than a single person and they can wander the map separately
‘Baldur’s Gate 3’ Prepared For 100,000 Concurrent Players, They’ve Gotten 700,000 (www.forbes.com) angielski