Nine times out of 10, the problem is all around the sleep prop of getting to sleep on a bottle or a breast. Unfortunately, if you don't break the connection babe has between their feed and sleep, it'll make the whole process harder. It will cause unnecessary night wake-ups because when babe wakes up in the night, she'll still have this idea that she needs a feed in order to get back to sleep at night.
A few things you can try.
Number one would be to move the feed up in the bedtime routine.
Most people have the bedtime feed as the last step. That can be really tricky, especially if baby does not have great napping routines yet, then she could be really fatigued by bedtime.
By the time she's had a bath, you've got their PJs on, you've read some stories, and then you're going into a feed, she might be way too fatigued to even attempt to stay awake at the bottle or breast. And that's when you're really fighting an uphill battle where you're tickling and talking to her and trying to keep her awake.
I would suggest you can even move it up to before the bath. Go to the feed, then the bath, PJs, stories, and then bed (always my suggestion if bub is over 3 months!). That will really help break any connection she has that the bottle or breast has anything to do with sleep. If that seems like a bit too far up in the routine, then move it to right after the bath. Most children really like their bath, so she'll be a little more awake when you get to the feed.
You can then move onto the next steps of self-settling. The good news is that once naps are better established, the less fatigued she'll be at bedtime, so that's something to look forward to. The more the separation between the feed and sleep develops, the less likely she will be to even try to fall asleep at the feed. You'll find in a month or so, even if she is really tired, she won't use the bottle or breast. There won't be a connection there anymore. She'll happily have her feed, and then put herself to sleep just fine when she gets to the cot.
I hope that helps with even a little part of your bedtime routine. Moving on from this, you are wanting to find a technique you can use with your little one to encourage self-settling. This absolutely doesn't need to be CIO (cry it out) or even controlled crying! You don’t however, want to get into the trap of replacing one habit with another.
Consistency is key here so babe starts to recognise and understand the changes.