XT-Xinte is a bit different than other affiliate platforms. You don't need any kind os special affiliate account. Just register your account there and you'll become affiliate automatically.
You will have to get Affiliate ID from an affiliate link.
Navigate to your XT-Xinte affiliate page. Near the bootm of the page, you will find field with your affiliate link
https://www.xt-xinte.com/?parent_user_id=593841&utm_source=sns_share&utm_medium=share_url
parent_user_id=593841
(in this case 593841
) That number is your affiliate ID
All you need is to copy that Affiliate ID, open extension options, go to Platforms / Chinese / Other, and paste Affiliate ID in the XT-Xinte field.
Then close options, find the product on TomTop you want to share and click on the extension icon. It will generate an affiliate link for that page. Then you can use bit.ly to shorten that link (if configured) or copy and share it.