How do I even approach divorce?

My spouse and I have been married for ten years. It was a quick, we met in the fall and were married by summer. Three months later we found out I was pregnant. Every thing moved quickly. We’ve been through job losses, living with his mom until our house was ready for us to move into, and him working 3rd shift our whole marriage. Which is where the breakdown comes to. An example of our Monday- Saturday is- I wake up at 6:40am daily, get our girls ready for the day, take one to school, and get myself through school. While cleaning, cooking, my own school work and classes. I also make sure he is awake at noon, I pack his lunch, and get him out the door by 1pm. Meanwhile he is gone I am still making sure everything is running smoothly at home, trying to get my law degree done, and making sure our kids are fed and clean and homework is done. He gets home at 10:30pm, kids are already in bed, and he is demanding that I heat up his food, and spend time with him, while I’m trying to finish my work for classes and am just dead tired. He is up until 4am sometimes 7am. He doesn’t help with our kids, nor the house, he wont even put gas in my van after he uses it and returns it on empty. I don’t ask a lot out of him, but a little help. And when he is home, which is Sundays, he is on Discord and or playing DnD online. And while he is doing that we must be quiet so no one is distracted by our kids playing together.
I didn’t sign up to be a married single mom.
Our oldest keeps asking when we will get a divorced because she’s scared of when dad yells at us, and she doesn’t think he loves her. I am constantly telling her that he does love her, that sometimes his emotions are stronger than ours and he doesn’t know how to handle them.
I’ve brought it up, to him recently, I told him that I am not happy, I need help, I don’t feel valued, and I am so tired of being on my own, and I just want him to go to bed earlier and wake up earlier and help or spend time with our kids for a few minutes a day. And all he got out of that conversation and replied with was “I don’t go to bed that late”. I’m not arguing anymore. I’m too tired.
How do I even go about bringing divorce up to him. I will legit leave him the house that he bought and everything, I just want a chance of finding someone who wants to be with me and my kids. We’re in Michigan if that matters. I don’t want anything from him, I just want me and our kids to be happy. We’re not happy. We’re walking on eggshells and honestly my kids keep making comments about how unhappy they are, and how they don’t think he loves him. It’s heartbreaking trying to convince them that he does.