Not give a shit.
Glad I could clear that up for you.
Also, you shouldn’t really be assuming gender anyway, because it’s literally impossible to always accurately guess it. There’s also the problem where gender and pronouns aren’t directly tied, and what you probably want to know is what pronouns to use.
Remember: If you don’t know someone’s pronouns, it’s usually safe to use singular they. However, if you can ask or they tell you, only use the pronouns they say to — to use anything but what they want you to is just fucking rude.