How to get baby to sleep through the night

Hey fellow August '18 moms.

My little guy is still up 1-2 times per night to eat (he is almost exclusively formula fed due to my nearly non existent milk supply).

My older son was sleeping through the night by like 8 weeks so I'm kinda lost here.

I work fulltime and me and my husband are separated so it's all me at night and I'm downright exhausted after 6 months.

He goes to bed around 8:30 & gets a bottle then. He is sometimes up at 1am & 4am, and other times only up around 3am.

Any tips/ideas?