Hi Metasheep, there's lots of places in Sardegna, try googling
Surf Sardinia some sites have lots of spots and quite often have arating for skill level.
I don't know Sardinia but I do know islands are very wind sensitive so you will need to learn about which winds for where another thing for you to learn is the long direction of clear water in any direction from the coast can determine how big the waves can get. Obviously if a storm is right on top of the beach it can be big and ugly and no fun but if the storm is a long way away and has a clear direction to send the swell to the beach it can generate beautiful and shapely surf.
Names of spots I know of in Australia are Buggeru, Minicapo but they are expert spots liable to scare you parents to bits. I'd give the entire west coast a good search and if you get to a beach and the locals are friendly ask about other spot.
Porto Pollo is rarely going to generate surf but Chia looks a much better bet, I had a look on Google Earth and it has a sand beach that looks to be able to catch swell.
Since you have a computer have a good look

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