Simple inventory tutorials ?

Looking for a tutorial about implementing simple inventory (suitable for SP and MP) as seen in older FPS games (Doom, Quake, Unreal, etc.)

Basically player picks up (one way or another) ammo, armor, keys, weapons, health, etc. and it’s all stored somewhere. Weapons are switchable using either keys (or scrollable using mouse wheel or some two keys/buttons), ammo is corresponding to each weapon. The rest is automatically associated with whatever it needs to be (armor pickups with armor value; colored keys just sit in the inventory; etc.)

UMG GUI would show either count for inventory items or icons + count.

Are there any tutorials available for such system ?

Thanks

You can learn the basic here:
Inventory UI with UMG