Sorry you're having a rough time right now- although most babies do it at some point. Mine was a terrible sleeper until he was about 6 months old.
Only real suggestion is try different stuff, and see what works for you- lots of people have different idea, but different things work for different babies. We had to do some sort of sleep training around 3 months, until then little guy was nursing to sleep then I would put him down. But over a week, I couldn't put him down without waking him up anymore, getting him to bed was taking hours each time and getting worse. But we didn't want to let him cry it out. Tried putting him down to sleep, and staying with him until he fell asleep. This didn't work at all, he pretty much stared at me, obviously if I'm there I should be picking him up. So we started leaving him, letting him cry for a few minutes, and them coming back to get him settled again. Took forever the first week or two, but did actually work without him being too upset/left to cry. We would slowly increase the time we left him before going in my a few minutes each time. Eventually he would go to sleep really easily, which was great.
However, at 6 months he was still getting up every 2-3 hours to eat- which was killing me, and was also totally unnecessary at that age. So back to trying stuff. First, I tired getting him to eat more before bed, and when he got up. This also didn't work at all. If anything, seemed to convince him he was starving to death, and after a few days started getting up even more often. So I started picking one or two feedings a night where I would cut him off a minute or two before he would normally be done eating. (Had to do time, because he was breastfed- otherwise volume would be easier) He would be full enough he wouldn't be too upset, and go to sleep with maybe a few seconds of fussing. Over a number of days, I made those one or two feedings shorter and shorter, and he started sleeping a bit longer. Soon, we had cut one out, and I picked a new night feed to shorten. Took a few weeks, but he finally started letting me sleep properly.
No idea what will work for you, but maybe try a few things that you both feel comfortable with, give it at least a few days to see if it works for your little one, and don't be afraid to try something different, because they're all different.
Best of luck!!