Different foods have different containers: Coke, beer, soft drinks often come in metal cans (or tins - depending on the country). Whisky, wine and juice usually come in bottles (glass). Chocolates usually come in boxes (made of cardboard) Biscuits and dried foods often come in packets. Etc.

In this example "can" is not a verb (I can). In this example it is the name of the container (bottle, glass, can, pitcher etc). It is referring to the metal container, not the verb.

Because coke comes in a small metal cylinder, which is what we call a can.

Can literally means “lata” (in Spanish). You know there are other uses for that word, but don’t forget it is also a noun. A can a coke (una lata de soda).