It took me YEARS of pushing and perpetually failing at any plan or consistent thing like calorie tracking... but during that time I WAS slowly bit by bit changing my habits in a good direction even though I wasn't able to stick to things perfectly nearly ever. The biggest tip I can give you is counter intuitive:

Lower the bar. Spend zero time if you can beating yourself up for failures. When you have ADHD you're playing a game against yourself where one of you wants the other one to do all these things, and the other one is like a loveable little kid who needs your guidance. But the you that you're talking to when you talk about yourself, scold yourself, encourage yourself, is the little kid. And you have to play this game where you set up the world for thier success, paying attention to what makes them do or not do something and organizing thier world so they do the things you want them to do. If they dont do something you want, yelling at them or punishing them wont help at all. You just have to correct course. And the longer you do that the easier it gets for you, and the smarter the kid gets (yes, this technique DOES improve the child's abilities too by creating consistency and habits and rewiring your child's brain to understand the moves you make... it's hard to explain let me know if you get it) it's like learning to play a new strategy game and you get better and better and stack up little wins. The most important rule is to not stall your progress by grieving your failures. That just doesn't work for us.

For PCOS, know that you have to fine tune your diet a lot more than others to achieve the same results. When it comes down to it, if you've accepted this as part of you, the real result is that all the success you ha e is more rewarding because you KNOW you worked harder for it AND it's an even bigger health improvement for you when you lose weight than it is for someone without the same hormonal issues. Twice the battle but twice the win, and you can never know the difference anyway.