If you want to get the most out of both yourself and your weapon, in Control, then you need plenty of resources and mods. Mods are used to increase your powers and abilities, increase heals from health crystals, and change how your weapon performs. Resources can be used to build new Mods, so they are always useful.
Control – How To Find Mods And Resources
The first and most obvious places to get resources is from enemies. Dead enemies can sometimes drop resources that you will pick up just by walking over them. Enemies keep a steady stream of resources coming your way.
Mods can often found in the hidden containers scattered throughout the world. The containers are a grey/blue steel, with a yellow caution sticker on the side. By interacting with them, you can open them, and get a resource or mod from within.
You can also upgrade weapons and mods at control points you clear. Interact with the control point, and select the Astral Constructs Tab. This process allows you to construct new types of guns for the Service weapon, or upgrade ones you already have. Switch options will enable you to create random mods or enhance existing ones. Random mod creation can be hit or miss, and you should probably focus on upgrading ones you find in the game world.
To equip mods to both your character and your weapon, bring up your Inventory (G on PC), and you will be able to select which mods you wish to place in the appropriate slots. Just click on the slots to see a full list of available mods, then hover over the mods to see what benefits they give you.