You could do the shopping and buy healthy foods

You can still have sweets but just cut down on them.
You shouldn't feel bad about saying no, it's a good habit to get in to. I know it's hard but once you start saying no you'll be used to it and won't mind doing it more often.
You don't have to do running to loose weight. Try going for walks, even if they're not far. It still counts.
Try exercising videos or get a mini trampoline and just sorta jump to some music!
Dance round like a maniac

So long as you're doing physical activity and moving, it's exercise really.
If you do that and balance your diet it should work!
Drink plenty of water!!
I hope that helped a bit
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