In Baldur's Gate 3 you can romance Shadowheart, Astarion, Wyll, Gale, Lae'zel, Karlach, Halsin, and Minthara, which is pretty much the full recruitable party with the exception of Jaheira and Minsc.

Specific actions and decisions affect romance outcomes with companions like Gale, Wyll ... for progressing romance with ...

The Astarion romance path is great, but his friendship is a gift. Without getting too technical, Magnetuning says that Astarion's Grinch face doesn't appear if you have graphical settings to ...