It is possible - when my children were young, including newborn, my husband worked away from home a lot. Thankfully for me, he would be away every week but home every weekend.
For me, the trick was to go with the flow and limit my expectations on myself. I have two pieces of advice, if you want them?
Make baby’s feeding times a treat for your older child. For us, it was reading time. I had a basket of new books, and during feeds I latched DS on and DD could snuggle up with me on the sofa and we would read until DS was done. Then we put away the basket and only got it out next time. So it was always ‘special’ for that time, when I couldn’t have been following DD around the house and needed her to sit still and engaged. She loved it - it wasn’t DS’s feed time, it was her snuggle time. Your son is a bit older, so his treat might be different, but you know him better than anyone, and what will ease things for you.
And - buy microwave pasta and rice, because there will be some days when boiling a pan of water is too much to do. But by having those and portions of leftover curry/casserole/whatever in the freezer I knew I and my toddler could eat well with minimal effort, and the rest just followed. That, and Mars bars and cereal bars and bottles of water in a basket in the bedroom for me, during night feeds. I was often ravenous then, and when I needed sugar or carbs, I needed them straight away and easy access.
It was harder when DH was away after I went back to work, but on maternity leave you really can please just the three of you. Figure out what you need, and the rest can be ignored.