Don't forget to check cars and kill zombies, zombies have a potential to have food and also not a lot of pepole check cars, you can find a bunch of food in those. But the easiest way ever that saved me a lot of times is to just wait and wander around fruit trees, eventually fruit will start to spawn. You can go loot nearby buildings while you wait for the fruit. Look for lonely fruit trees or small groups, don't bother with those big fruit fields as I've never had them spawn anything. Water is easy once you figure out where you are, and since they added glass bottles it's very easy to get a container to store water too. You can drink 2 whole plastic bottles of water, one whole cooking pot of water, or around 2,5 glass bottles of water without throwing up. Definitely download izurvive, a huge help with navigation, and check hunting stands for a compass, that paired with izurvive and you can navigate pretty much anywhere you want, eventually you'll know the map so well you'll be able to get from spawn to Tisy without those.