‘Baldur’s Gate 3’ can be a fantastic experience and a bad game at the same time.
I know of three instant game end dialogue options. One with Astarion, one with Volo, and one in the House of Hope. I think there might be a few more as well.
There’s also one with Mystra I think.
There’s also one in the githyanki creche. If you aren’t nice to >!Vlaakith, she casts wish on you and kills your entire party instantly!<