Am at exactly same stage as you, with a 2.7 year old and a four week old. It is hellish.
I lay out on our kitchen table the stuff needed for breakfast the night before.
I try to feed the baby first thing whilst my husband gets ready for work, and then my husband will burp/jiggle her whilst I shower and dress quickly.
Get toddler up, give her breakfast in her pyjamas whilst simultaneously trying to top up baby and feed myself. (If toddler gets food all over her pyjamas it doesn’t matter as will still need to dress her, but if I help her get dressed before breakfast it can mean a second attempt at dressing her if weetqbix goes everywhere 😁).
Baby will normally go down in her vibrating bouncy chair thing, then I can do teeth/tidy up for five minutes.
This morning in the rain we played inside with dollies and read books. When toddler was happily playing changing a nappy, I nipped off and made her a sandwich for lunch and popped it in a box in the fridge - basically if the toddler is entertained for any stretch of time without me, I use that time to tidy/make food/etc.
Had lunch late and got toddler supper out of freezer, once toddler down at 1.30pm for a nap. Currently feeding baby whilst I read stuff on my phone. 😊
Will set up colouring stuff on coffee table before I get toddler up, so that have easy speedy entertainment when I need to feed the baby again.
Much of my days I just muddle through at the moment, but trying to be one step ahead seems to help a bit currently. I will leave baby to cry for a minute or so (as long as it’s not the hysterical crying) if it means that I can get something done with the toddler that will give me ten minutes peace with the baby after that.