Do I really have to make hundreds of triangles per item?
Forum error FE001 Question Ambiguity
If you are piecing your meshes together procedurally then yes.
Normally you will get mesh sources elsewhere, like from the Asset Store, or made yourself in programs like 3DSmax or blender
If your question means ‘Does it really take hundreds of triangles to draw an object on screen’ then yes. This is normal.