Okay the good news... Its more like coping with 1.5 babies! You feed one then the other...or both at once if necessary. Change one then the other etc so its only one trip to the changing mat or getting stuff out.
Routine is essential. My eldest was 2 when the twins came. I survived with lots of distractions for her whilst I did the practical stuff for the babies, resorting to baby TV on occasion. I kept her in nursery part time, which whilst expensive kept me sane! I was stricter with sleep routine, unlike with my 1st, so I could have quality time with the toddler.
I had a tote bag for when I was feeding, stuffed with fidget toys, and favourite books. A big comfortable armchair, I would read to her and she would snuggle in and turn the pages. All went back in the bag until the next feed. It meant she saw that as Mummy time, with the attention on her, rather than something to compete for.
When people arrive and ask to help give them a specific task. "yes please! Could you pop the washing machine on? Make me a sandwich as I haven't eaten?" Don't be shy, otherwise you will end up running about making cups of tea, whilst they sit there.
We were lucky to have them all in bed by 7, so I would flop on the couch for a few hours. I would be asleep by 9!
The first few months are survival mode! Husband was in charge of food shoping/meals/laundry. I had a cleaner twice a week.
My focus was recovering, and the wellbeing of the dc.
Ill pop back if I think of any practical tips x