Sleep is a nightmare

https://www.todaysparent.com/baby/baby-sleep/2-month-old-sleep-training/

I used this to sleep train before the regression then after my sons regression we had to redo it

Let me quickly ask you a few questions
Is he overtired? Getting enough naps throughout the day? Overstimulated before bedtime? Do you have a bedtime routine?

overtired yes, bedtime routine yes, i don’t think he’s overstimulated and he gets enough naps throughout the day, but he wakes up late in the morning so i don’t know if this is causing him to also sleep late in the evening

Definitely try something like the huckleberry app to make a consistent sleep schedule. Just put him to bed whenever it tells you or when you see he is tired. Also if you are bathing him before bed try switching to the morning, maybe he is one of the babies who finds bathing stimulating. You can also try moving bedtime. Before my sons regression bedtime was closer to 10, after we moved it to 7/8 and it helped him sleep longer without waking

Agree with the huckleberry app. I’ve been using it recently and seems to predict naps fairly well. The more overtired they get the more they have cortisol in their system the more they resist bedtime or naps. And even if they go down for a nap it’s not restorative and they may wake up still needing more sleep or tired. It’s a freakin annoying as hell cycle. So try to get them to nap before they get overtired. Easier said than done. I myself have been stuck in the overtired rut for a while now and have been resorting to watching my baby like a hawk at the first signs of sleepiness. Once naps are restorative they fall asleep at bedtime easier and stay asleep longer as well.
Agree on the bath being overstimulating as well though it he does get excited in the bath but falls asleep nursing after so I’m not cutting that out just yet.

What time does he get up in the morning? You might be right that could be contributing to late bedtime.

9am

You might’ve tried but did waking him earlier help or may help if not tried?