co sleeping

I am struggling. My little guy is breastfed and we currently cosleep so that we "breastsleep". He wakes up every 2.5-3 hours to eat and then immediately goes back to sleep. This is exhausting still, I have two other kiddos and I feel like I never spend time with my husband after the kids go to bed because baby doesn't sleep that long st a time. Do I need to sleep train? If I moved him out of my bed would he sleep longer? He's my last baby so I'm having a hard time with this as I know he's only this small for a short time 😔