Lae'zel is the first party member players meet in Baldur's Gate 3. She helps the protagonist through the nautiloid ship during the prologue, and players can recruit her into the party permanently by helping her escape her captors near the nautiloid ruins.
Baldur's Gate 3: How to Romance Lae'zel Guide
Lae'zel is a prickly party member, but she can quickly come to appreciate the protagonist with the right approach.