It's really hard. My 9 month old has always been like this. We always held and rocked her to almost asleep and put her down, but she was resisting more and more and it was taking 45 minutes just to get her down for naps and 2.5 hours to bedtime. It was killing us. She always slept though the night once down, but naps were a joke. Rocking for that long and being screamed at and hair pulled was killing us.
A few days ago I finally decided to sleep train. Give her a cuddle, same white noise, dark room, sleeping bag, but pop her down and leave the room. Then we did ferber, go in and check at 3, 5, 7, 10 minute intervals, but only if she is continually crying. If she's stop start whinging, you leave her to it. When checking on her, go in, just reassure don't pick up, and leave again.
Did naps and bedtime together. First time was her first nap of the day. It was hard but didn't even get to 7 minutes before she actually fell asleep herself. She's not done that since she was born.
We're still establishing it at the moment as only been a few days. But I wish I'd done it sooner. No longer am I a stressful mess with a broken back. And DD actually had a 2 hour nap yesterday? Unheard of!
Do what works for your baby. Good luck