I don’t want any kids but my mom is annoying me

im her oldest , im 23 and shes been bugging me and other people how badly she wants grandkids blah blah. I want to adopt around 30 and right now i’m in college and trying to get a good job to provide for myself and my boyfriend. So i don’t get why she wants me to have kids. Mind you she had me at a young age 17. so she thinks i’m goin to have a kid at a young age. how do i make her shut up already? And also my grandma has been mentioning to me how she wants great grand kids before she dies. Uuuhhhhhhh bro. What is going on with these women in my family ?!??