In terms of sugar, I've had some success replacing it with healthier options like Stevia but really just lowering the amount of consumption helps. I find that if I stop having "sweet" did for a while I am much happier having more savoury snacks and it becomes harder (or less desirable) to return to sweet things. I have some healthy eating resources I can probably scan and share if you would be interested.
Snacking on protein instead of sugar really worked for me cutting down on sweet stuff. Now not only do I not crave sugar, but I find sweet stuff pretty nauseating, generally.
Even something as simple as some carrot sticks can be great to fill that hunger craving, my default action now when I am hungry for a snack is to check the cupboards (learned behaviour, must stop, naughty naughty) and make myself a large glass of water. That not only helps fight the craving, makes me feel refreshed, but also removes me from the kitchen so I'm not tempted to go back for a sugary snack.