Newborn(3week old) and 3 year old

My husband goes back to work in a week and I am so nervous about being home for the first time with two kids. I’m exclusively breastfeeding and I’m just now getting better with her feedings.

My 3 year old has been peeing on herself/the floor/rug and has been trying to hide it. This started two weeks after new baby was brought home. She’s been using the potty before but now I have to fight with her just to sit on the toilet.

Do you have any tips or advice for new life with two kids?