Sleep

They will eventually; some take longer than others. I assume you're talking about night wakings, because "self-settling" is something different - it means to be able to calm yourself when you are dysregulated. You first start to see this in toddlers when they start to push you away instead of clinging to you when upset; it's their first attempt at calming themselves rather than relying on co-regulation. The reason people connect it with sleep is because they only notice babies waking up if the baby is already dysregulated and crying. You likely won't notice if your baby happens to wake up and go back to sleep on their own, without any noise or intervention from you. (C)

Generally you get to know the difference between "fussing" and full on dysregulated crying; the key to letting them figure out how to settle is in the fussing. If they're fussing, not crying, give it a few minutes. Go to the bathroom. Let yourself wake up. Have a drink of water. If they haven't settled, or if they get worse, then go in and assist. But if they aren't quite dysregulated yet they may figure it out on their own.

This might not be relevant for you, but I did notice around 8-9 months that mine wasn't actually waking up, but would cry loudly in her sleep. If I went in at her cry, I would wake her up and we would be awake for hours. If I gave it a minute she would likely just go on sleeping like nothing had happened. Babies are weird that way.

Sorry for the ramble. Tl,Dr; you don't have to "teach" settling, or sleeping. Everyone sleeps. Some babies just need a bit more support than others.

You can’t teach sleep - self settling is largely temperament base and self soothing just can’t be done by little ones! Sleep is linear so changes constantly, a lot of it is temperament, sleep needs, environment and sleep hygiene. I’ll add a few links below :)

https://www.instagram.com/p/DOJGRyYiJQ0/?igsh=em15ZWx0aGpnMzJm

https://www.instagram.com/p/DKhE0c2I4gC/?igsh=NG9jODF4dm9tdXQ0

https://www.instagram.com/p/DFXyRyooo7p/?igsh=cXRwMzZobTVqanE4

https://www.instagram.com/p/DCG-WI7oPcu/?igsh=MW5vcjdsM2J0aDNjMA==

My first suddenly started sleeping 12 hours straight just before he turned 1. I never sleep trained or even attempted to get him to sleep through the night

14 months she started sleeping through. We still bed share with a side cot and she sometimes wakes up to snuggle closer but doesnt need much now. Unfortunately think she has hit a regression at 20 months.

We alway encouraged self settling and have never sleep trained. He’s now 1 and has been sleeping through the night since 7 months. He was putting himself to sleep for naps and nighttime from 5.5 months. I was adamant not to have a sleep association like rocking etc and in the early days we would stroke his head. Then we just sat next to him and by 5.5 months he could be put down and would go to sleep himself.

All babies are different though and we’ve been incredibly lucky to have a good sleeper.

It is developmentally normal to wake in the night until age 4 and under one it helps prevent SIDS.

The thing I find works best is a good routine in terms of timings/wake windows.

At 6 months we stopped going by sleep cues and introduced a clock based schedule based on what worked well for her.

What is the current routine?

Just noticed you said she’s 6 months, has she started solids, and is she feeding through the night (Breastmilk/formula) ?

Don't mind a long comment.

Id say the jump in wake windows is a bit long. Generally as it gets longer during the day it would go from 2 to 2.5 then 3 not 2 to 3 then 4.

Id try wake at 7
Nap at 9
Next nap 2.5 hours after this
Nap
Then wake window of 3-3.5 before bed.

The first nap being short could also be a sign she needs a longer wake window beforehand. Ideally you'd want a longer nap in the morning. This is quite early to be on 2 naps too.

What sleep cues does she show?

Eye rubbing is one of the last signs of tired so ideally they'd already be asleep by then. Id keep an eye on when they are shown and offer sleep like 15 mins before so they fall asleep then.

Just for info I can see you've mentioned weaning on baby rice. Baby rice has no nutritional value and is just a space filler which would be better filled with milk.
Better to start with vegetables and fruits.