Well I certainly can't give any good dietary advice. I wouldn't say I was unhealthily fat, but I'm sure a doctor would. And I have noticed when watching Love Island that I seem to have a different physique to most of the contestants.
I definitely don't want to take away from francij and Dave's sensible advice. As francij says we have been subject to propaganda for at least 80 years, and the advice keeps changing. Eggs being a notable one for going in and out of fashion each decade. I've just seen a doctor on tiktok (probably not a peer reviewed scientific channel) saying ignore everything you've heard about cholesterol.
When it comes to salt, only 25% of the population are sensitive to salt. Yet we have politicians looking pompous and proselytizing about salt, taxing it and giving us all advice about it. I say give everyone a salt sensitivity test on the NHS help the people who need it and let the others get on with their lives. Apparently 90% of people eat twice the recommended salt intake, but I really can't see why there is a recommended salt intake at all for the 75% of the population it doesn't affect.
So my advice is whatever is currently considered good dietary advice you can ignore because it will change tomorrow.
Our ancestry suggests we started in trees eating fruit, then ate some meat, did a bit of cooking, and quite recently planted a bit of wheat. We have partially evolved to cope with these changes, but let's be honest we haven't even evolved to get the walking on two feet sorted yet, and the digestive system really needs a makeover. As far as evolution is concerned living long enough to produce two offspring is considered a success, anything more is a bonus.
Whatever you decide to eat make sure you enjoy it.
(p.s. I know even if you're not sensitive to salt eating a kilogram of it in a day will kill you)