Expect things to NOT go smoothly. Just roll with it. Sometimes I pretend I'm the hired help so I can keep my cool. Truly.
If you can get outside, do.
At the start, focus more on the routine and moving from one thing to the next rather than what is actually being done during that time. So, if he's supposed to make his bed and pick up his room after breakfast, set at timer and focus on engaging in that activity, rather than doing that activity to completion or even doing it well.
Have set times for snacks and/or set areas for eating. Don't start a free for all with snacking.
If you want a set curriculum where it's all online and planned out for you. Monarch has a 30 day free trial. They will populate the calendar for you, grade most of the things, etc. The regular lessons are a little dry but the projects are pretty fun. If you decide to continue it I think it's $25 a month for all 5 subjects (Bible, Math, Soc St, Lang Arts, Science).
https://www.aop.com/freetrial/enterpromocode