Getting ready to CIO with my 14 month old

Hi everyone!

I have a 14 month old son who used to be a great sleeper up until 8 months old. He always needed contact naps during the day but was able to sleep through night in his crib. Ever since he turned eight months old, he has needed to be held and will now only sleep through the night if he is in bed with my husband and myself. This has been going on long enough and I just need to break the cycle for my sanity. I just need some advice regarding sleep training since this is the first time I’m doing it. I have scrolled this sub Reddit and have found a lot of useful information, but I just wanted to run it by everyone to see if anyone has any other advisor input.

He currently has a wake up time at around 7 AM. His first and only nap usually runs from 11:30 AM until one or 1:30 PM. Again, his naps are only in bed with my husband and I. After that, he stays up until 7:30 PM. I know the last week window is long and I have tried to push his nap back so that he naps later in the day but he consistently is just ready for a nap between 11 and 11:30 AM.

I have tried the check-in method and he just seems to get more upset and he is literally screaming his head off if I ever come in to check on him. At this point, do I just try the extinction method? I just want him to be able to sleep on his own without needing to be in bed with us.

Thank you so much.