I'm sorry you've had to make this decision in such a hurry. It must feel very unsettling, but I'm sure you're right to have done it and that your son will start to feel happier soon.
Just focus on right now. You don't have to have long-term plans. That can come later. There's no hurry. Or you can carry on just doing it month by month and year by year and never have long-term plans. At any point, if home ed doesn't feel like it's working out, you can tinker with it to make it better, or you can always send him back to school - maybe a different one if his original school was a particularly bad fit. Some kids who didn't thrive in primary are okay in secondary.
Other parents who have removed their children from school usually advise starting off by taking a complete break from all formal adult-led academic work, especially if the child had bad school experiences from which he may need to recover. We call it "deschooling": getting the school out of his system and yours. Give it a few months at least. Just let your little boy have fun and do all the things which make him happy. Play with Lego, read to him, take him to his favourite museum, cuddle the dog, play video games. He needs a reset before he'll be feeling calm and contented enough to sit and focus. These things are all learning experiences.
Some families like mine never do move on to school-style learning at home, but continue to let their children decide how and what and when to learn. If you do want to do more formal work, you could introduce different subjects gradually once you think your son is ready, maybe starting with his favourite subjects so as to get off on the right foot, or you could do projects based on his interests and cover all subjects through the project. There are many many ways to home educate, which you can start researching and considering while your child is recovering.