I think the best way to know how to train him would be to contact the Italy National Team manager and ask him, because he could give you the best guidance on what you need him to look like in order for him to make the team in the future. I personally would tell you to get his three big skills (Rebounding, Inside Shot, Inside D) all up to 16 and then work from there, but the Italy National team manager may have a different idea in mind, so I highly recommend asking him.
Murray/Harris/MPJ/Grant/Jokic - 2020 NBA Champs