Sleep Training Tips

Hey, I'm a first time momma. My baby girl is now 17 weeks old (about 1 1/2 weeks shy of her official 4-month mark). She used to be amazing at sleeping through the night starting at about 11 weeks. Now she wakes up at LEAST 4 times a night. She's exclusively formula fed due to circumstances out of my control surrounding her birth. She used to take a really long nap in the mornings (like 4 hours) but now she really only wants to sleep max an hour per nap. I don't really follow a wake window; she was always pretty good about just falling asleep for naps. The past few days i have tried to keep wake windows to a max of 2 hours, but there's only so much i can do to actually get her to sleep 😅 Our current bedtime routine is 6:30 bath, one last feed, put her down drowsy usually (my husband handles nighttime putdown so I am unsure if he does something beyond that.) Because we have such a tiny space, she sleeps in our room. She usually wants her binky to fall asleep. Does this disruption mean she is ready to sleep train? How do you sleep train? Does cry it out include not putting the binky back? Should we stop responding to her cries immediately, and just let her scream? It's been a week and we are oh-so-very tired. I am trying not to feed her at night unless she just absolutely will not sleep at all (she eats quite a bit during the day, and she always falls back asleep quickly with the binky). She's been waking up around the 6 am mark but with the binky i can usually get her to sleep another hour after a few tries. Any tips are appreciated.