Putting themselves to sleep?

Okay you guys. I need HELP. All the advice.

10 months old, breastfed and formula fed.

Up until about a month ago she willllll notttttt sleep longer than 20 minutes for naps and 2 hours during the night. She’ll wake up after bedtime and all she wants to do is nurse. Even if she’s half asleep. I KNOW she’s tired, she has to be. But I have no idea what to do. I’m pregnant with #2, 5 weeks, and I’d love for her to get her sleep as well as me get mine.

If anyone has any ideas how to start getting her to sleep on her own, pleasssseeee let me know.