What is the role of the golgi apparartus and endoplasmic reticulum in the seletion of proteins?

Answer 1

Proteins are made by ribosomes attached to endoplasmic reticulum (ER), then this ER matures them and sometimes adds other molecules to proteins, like sugars, metal ions, etc. So when they are ready to be exported, they are packed into the Golgi apparatus, then selected into the appropriate moment to be excreted.
So thy ares selected in shape, function and concentration by these two organelles.

Answer 2

ga packages proteins and sends em to cell and stuff andoplasmic reticulum is where it goes thru and is covered in robosomes witch make the protein