The TS6 server files that are required to utilize screen share are not yet available for self hosting or available from an ATHP at this time. This will be coming out for users to self host in the near future.
You can currently use screen share via Peer-to-Peer in Group & Private Chats, and also on our Official Community Servers which you can find on the dashboard in the new client.
If you want your own server, then the Communities our directly hosted solution. There is a free trial option currently for the squad plan.
Communities can be found at myteamspeak.com/communities