Where can I buy Tez?

Could you please elaborate on the options available for purchasing Tezos (Tez)? As a cryptocurrency enthusiast, I'm interested in diversifying my portfolio and Tezos seems like a promising investment. Could you guide me through the various platforms or exchanges that facilitate the buying and selling of Tez? I'm particularly interested in knowing about the security measures and transaction fees associated with these platforms. Additionally, I'd like to know if there are any restrictions or limitations when buying Tez from specific regions or countries. Your insights would be greatly appreciated.