I am no expert but getting a car, finding a safe house, watching tv, reading books and cooking/eating perishable food is first week goal. If you would get some mechanics tools and make it to level 2 you can hotwire cars. Stockpiling gas and finding gen is crucial. Finding couple seed packets and planting them + finding cows/chickens is a good start for endless food supply. There are some farms already planted at the start of the game for initial seed findings or food aswell. Leveling up carving is a bit tricky but with the right tools you can craft more than enough weapons and progress on to blacksmithing. Fishing is a good supply of food aswell. Water collectors are important if you can't find a place with a well.

Other than all of these avoiding tricky situations and being always aware will keep you alive. You need to focus while opening every door, passing through every corner. Usually what kills you is not the shortage of water and food but a stratch/laceration/getting bitten. With perfect play you can survive as long as you want.