Metal Gear Survive may not live up to its name, but it is not too shabby by itself. While not a stealth focused game like its predecessors, it can be challenging at times. Here is a few tips on how to go through the rough patches with ease.
Your character will be on the verge of starvation from the moment you set foot into the game proper. The game will give you a quick, one-mission-tutorial on how to gather food and water. Your character is a glutton, so both the hunger and thirst meter will be going down quickly. You will have to make the most out of your limited resources.
To that end, do not eat any meat until you roast it or cook it into a stew. If you eat raw meat you will gain only half the benefits compared to when you prepare it. Drinking dirty water will be mandatory up until Chapter 7 so just go for it. Once you receive a Canteen use it on regular basis, because it holds twice as much water as a normal bottle does.
Later in the game you will be introduced to different ammo types, such as Normal and Heavy Arrows or Regular and Over pressurized ammunition. If you're carrying two types of ammunition on you and run out of one type in combat, your weapon will not automatically load the other type. You have to do it manually - if it's a primary weapon hold 1 or if it's secondary hold 2. Then while you're hovering over the bow or gun, press E to change the ammo type.
Speaking of ammo, it's a rare commodity and you will mostly rely either on your melee weapons or your bow. Remember that the arrows you shoot can be reused, they will usually be found on the corpses of your victims, but sometimes they don't stick and you can find them in the vicinity.
In the beginning you might find spears and one handed weapon to be more effective, since spears can stab zombies through a fence and both weaponry types are faster than heavy weapons. Neither of them can kill five zombies in one swing though.
I would suggest equipping the Sledgehammer as soon as you get a chance and use a skill point to learn Combat Step. If you use Combat Step to dash towards enemies and then left click in quick succession, the attack animation will be extremely fast and any zombies in front of you will be dead.
The following paragraph contains mild spoilers for Chapter 14, skip over it if you don't want to see them.
During Chapter 14 you will be tasked to expand your Base Camp. In order to do so, you will need some basic materials you will likely already have in storage along with a small amount of Kuban Energy. What the game doesn't tell you though, is that you can't expand until you have scrapped every last bit of rubble inside the camp's borders. Make sure you scrap them beforehand so you don't lose half an hour trying to figure out if the game is bugged or simply lacks valid feedback.
When it comes to multiplayer, I would not suggest going in before reaching level 20. as this is the point where your gear will be up to par with health levels of Wanderers in your weekly and daily assignments.