You can buy it if you open an account. If you want to open a US stock account, you can buy oil futures and open an oil futures account. The specific account opening process is the same. Mainly choose a formal platform. The specific account opening can be found in the webpage link.

Application method: make an appointment to open an account.

Trading varieties: international futures, international securities swaps and futures derivatives.

Trading methods: online trading and mobile phone trading.

Custody banks: Bank of Communications (Hong Kong) and Hongkong and Shanghai Banking Corporation (Hong Kong)