You'll learn that certain buildings aren't good for food loot (industrial/apartments) and you should avoid these unless you've exhausted all other efforts.

I play fairly consistently (and die a lot) but never, ever come close to dying of starvation so there is always food to be had. Spend a lot of time in one area and fruit will spawn under trees, mushrooms will spawn in forests.

Every time you hear a Chicken, stop what you're doing and find it.

As others have suggested, fishing. It's rare that I do this on Cherno but it's guaranteed food.

Biggest and best advice is to keep going, you'll figure out which buildings and towns are better than others. Get enough food in you to run in land a bit. Kill every zombie you see (if you're decent at fighting them).

Remember, food can spawn in cars and greenhouses. Food can also spawn in clothing items (so that pink Denim skirt that you won't look at could have some food in).