In order to buy SUIE and hold on your Metamask wallet, you must go to Pancake Swap and select the cryptocurrency you have like BNB, USDT, .... and also SUIE crypto token.

Selecting the SUIE crypto token you need its contract address to be listed. 

SUIE smart contract address: 0x4BacC780D76c15aaD26fBcD1df8C750A2CC0bA69

SUIE smart contract address is available here: https://bscscan.com/token/0x4BacC780D76c15aaD26fBcD1df8C750A2CC0bA69