Starting out, stock up as best you can on water and food. There is the tutorial zone for food and water, but there are 2 more areas to get sheep and goats in the area you start in, as well as small gerbils running around. Just outside of the zone are a handful of areas on the Dust that houses animals and a normal atmosphere, meaning food and water.

Before you start going on more long endurance missions where you need a gas mask, be sure to top off ALL of your stats, including health and any ailments. Avoid drinking or eating untreated or uncooked food unless you are going to die without it and have a way to get back to base camp ASAP. You will be able to make tents within the first 5 or so data clusters. You will lose some food and water, but it is easier starting out than trying to scavenge medical supplies of one sort or another.

Don't underestimate basic fences, and always take at least 4-6 fences with you on expeditions. Makes life a lot easier if you have to go on the defensive, even easier using weapons that can do damage through the fence, which appears to have a slight AOE to targets on the other side, as well as bonus damage. Just block access points, and whittle down incoming wanderers.

Be sure to invest some of the Kuban energy you have into ranking up your character. Makes a noticable different from the get go. Focus on stat building for the first 10 or so, and pick up some of the more quality of life skills in the few levels where your stats are maxed until you hit higher levels.

If you find yourself missing some key component, chances are it is right around the corner and is tied to progression in the campaign, typically the data clusters.

Resources do respawn, seems to be once ever 8-9 hours or a day in real time, same for chests.

While out exploring, if you can get to a Charos Corps Chest, do so. Easiest way to get BPs and also a nice little bonus from time to time. Just watch out as they tend to have one Wanderer roaming nearby, and commonly one on the ground looking dead in rather devious places.

Silenced RANGED weapons are a must for any sort of expedition where you are in the dust more than a quick sprint. Trust me on this. Always aim for the head if atl possible. Heavy arrows are well worth an investment, costing just a little bit more than normal arrows, but they offer a fairly potent bump in alpha damage.

A prefered loadout for early game exploration is a bow, a melee weapon that has a bit of reach (shovel seems to work really nicely for this) and a sawn off shotgun for the secondary slot as a last resort.

For Iris Energy extractions, if you aren't sure about being able to hold out, build some sandbag pallets and encompass the drill spire itself with them. It took me 4 pallets to prevent incoming enemies to do direct damage. You can stand on top of these and hit Wanderers with melee with impunity. Just be sure to do it quickly otherwise your safe haven is going to get you stun locked on the ground. Please note this does not offer much agaisnt explosive enemies.

Be sure to break down old gear, up until you get the resource procurement team. Then start gearing them up to ease some of the resource finding load off you.

Co-Op isn't advisable until you have some starting defences and some of the starting gear strengthed to +2 or +4, simply due to enemy scaling.

Make sure to stealth kill enemies, finishers in particular, starting out. Use a finisher if you aren't absolutely sure that you will kill the enemy in your first go, especially if they have friends nearby. In Co-Op, this is especially important. Basic enemies tend to die in one hit to finisher from stealth, armored enemies are more or less stun locked, walking scrotums with legs aka bombers, don't explode if you do it right.

In Co-Op, secondary missions tend to start/spawn in the same general areas. Some of these have weapons, fortifications, vehicles of some types. The wormhole generator is infinite use, and can make life so, so much easier to get to these if you place them right at the start of the match before wave 1. Instead of a 2-3 minute treck depending on your stamina and gear, it takes literally seconds to get there, and makes the entire trip fractions of the normal time. Also worth noting that any friendly can use anyone else's wormhole.

If you can't kill enemies quickly in wave defense, a viable tactic is to just slow them down as much as possible so that the wave timer ends with no or as minor damage as possible. A good rotation for defense in situations like this is to have 1 person running and kiting through secondary missions, the other 3 delaying enemies with walls, and for bombers and detonators, claymore mines work wonders, just be sure to get away before the ballsack of death claims another victim. Repeat as necessary.

Mounted guns, and chainguns on the vital suits, can, and will overheat. The mounted HMGs (the ones with tripods) seem to have a good amount of over penetrations of targets, so use them against armored enemies, and large groups where a single bullet has the best chance to hit multiple targets. Mounted guns also have a limited ammo pool that appears to be shared with their durability, so mount them out of reach, and maintain trigger control.

Base Building, my guilty pleasure.

Pretty soon out of the gates, you are going to start having to care for other people. Build stuff as it prods you along, but be sure to organize what goes where and why. Learned this the hard way and had to shuffle stuff around for about an hour and a half to get it to where I like it but is still defensible.

A pretty solid means of organization is to use the sectors already arranged. Such as this
There is a surprisingly frustrating part of the campaign where you start getting some freedom with the base building but don't have any passive production of resources. Build stuff to start making food as you are out and about ASAP. Goat pens help a lot, and the goats will breed, in addition to supplying their full drop tables.