Sleep training tips?

Hey mamas! I am writing this post in complete desperation 😥 I am at a loss. I haven’t gotten hardly any sleep for weeks and I’m starting to see that I can’t be as good of a mom on no sleep 😔 My son will be 5 1/2 months on Sunday and since he turned 4 months old he is not sleeping. He just started sleeping right through the night before turning 4 months old. It’s only getting worse. The last couple of nights I’ve had to rock him for at least 1-2 hrs and during this time I’ve tried to put him down 10x over with him waking and crying as soon as he’s down 😞 he’s waking up every 1-3 hrs all night and refusing naps during the day so he’s constantly overtired. If you have any tips or suggestions or can tell me what you are doing I would be so grateful!! Thank you.