Treat him like a professional colleague, a peer in your team. You can’t allow yourself to flare up when he acts badly, but you can firmly and clearly stand up for yourself and ask him not I speak to you that way. With a colleague you would set expectations for who does what work, plan your time, work out what his strengths are and play to those. Make sure each of you get equal Time off for hobbies, exercise etc.
Also make sure finances feel fair, and get yourself into well paid full time work ASAP. Your baby is big enough for full time day care unless there are special needs involved. You may not add a lot to household income after you and DH share the childcare costs, but it is essential you are in the habit of working - good for you to be able to show you can manage a job alongside family, good for your MH, good for your kids to be used to you being the last to be collected from nursery/after school club! Assuming your goal long term is 50:50 shared custody, you won’t get as much financial support so you need to be independent.
For his sake, get him involved in all aspects of childcare including things like setting up birthday parties, buying gifts, arranging play dates, choosing (and paying for) childcare providers and extra curricular activities, selecting clothes and shoes, organising haircuts and dental appointments. You are much more likely to end up with 50:50 access to your kids if he is involved now, and it is great for the kids if they can have a very involved father, not one who disappears when they are young.