You can also try the plugins page itself. Once installed scroll down to the plugin and I think there is a Configure or Settings option beside it.
You may have to whitelist some IP addresses on your server as well. This is what I was once told by TikTok:
We detected you have a firewall on your server that may interrupt our service
Products imported from WooCommerce to TikTok Shop might be interrupted
Orders created fro TikTok Shop might not show up on WooCommerce
Here’s what you can do:
Whitelist IP address: 103.136.220.238/31, 103.136.221.238/31, 34.85.162.64/26, 139.177.251.0/28, 139.177.252.0/28, 103.136.220.0/24, 103.136.221.0/24
Whitelist user-agent: tiktok-business-plugin
I did the above and now I get taken to a TikTok page with a Connect button but when I press I just get 2 spinning circles and nothing else happens so there is still something wrong.