Surviving and Sleep with Newborn twins

We have newborn twins (4w) and are seriously struggling with sleep. Those of you who have done it before any advice is welcome. I browse this subreddit and it's always so helpful so really any guidance would be appreciated!

Any advice on bad acid reflux, one of our little ones has it rough! How you you actually feed them at the same time ? Advice to help with milk production? How do we start training them for sleeping moreat night ? When's too early ? When do you think about letting them cry it out?

I feel really lost right now and I really wish there were straightforward answers which I now that there isn't. Thank you!