It adds different armor, blocks, items, and more. It adds ore which can be used to craft different armor and tools.

This list includes the items in the mod. 
-Tacos
-Chicken Nuggets
-Blue Triangle
-Orange Triangle
-Stars
-Star Tools (Pickaxe, Sword, etc)
-Blocks of carrots
-Star armor (Helmet, Chestplate, Leggings, Boots)
-Power cells
-Triangle chairs
-Tables
-Triangle Pillers
-Star Blocks
-Star Ore
-Taco Ore
-Sidewalks
-Orbs
-Block Of Tacos
-Taco Armor
-Taco Tools
-Bedside Stand
-Triangle Toaster
-Counter
-Taco Chunks
-Doge
-Doritos
-Arm Chair
-Stove
-Milkshake
-Red Stone (not Redstone dust just red-colored stone)
-Red Dirt
-Communism 
-Communist tools and Armor
-Power Of The Soviet Union
-Vodka
-Soviet Fist
-Communist Flag 
-Hammer
-Sickle
-Communism Block
-Doge Block
-Doge Statue
-Coin
-And More Coming Soon (or not don't know)
 
Also, this mod is only for 1.12.2