trying to prepare big preps and stuff can put you into choice paralysis and will make it more difficult for you in my experience.

diets whether it be keto or paleo or vegan or vegetarian will also make the majority of people stop eating well after a week or two.

cut out sugar, it's a drug, you will want it but you don't need it so just toughen up and cut it out completely.

then don't eat anything that's in a package or processed, just buy meat / veg / fish / rice etc, it doesn't matter what just grab it and fill the basket.

start basic with just fibre for breakfast (maybe a wheat-based cereal or something) then just snack on fruits/vegatables throughout the day and have a really good meat/rice or vegetable dinner.

eventually you will crave sugar so if it's been a week or so go for something natural like honey or jams, throw it on a scone or piece of toast and it will satisfy the craving (try and limit yourself to 10g of sugar when deciding what you want).

everything else will work out its self, you'll start spicing the meat and frying/roasting the vegetables and will look forward to cooking but the most important thing is to fuck reddit and list-making and just go and do it.