Your going to have to code most of those features yourself since you likely will not find an out of box template. Chat is going to be the most difficult since you basically have to write your own chat client.
Chat: https://dev.twitch.tv/docs/v5/guides/irc/
Last Streams (aka Vods): https://dev.twitch.tv/docs/v5/reference/videos/
Followers: https://dev.twitch.tv/docs/v5/reference/channels/#get-channel-followers
Sub button is the easy part since you can just use a link to: https://twitch.tv/<channel_name>/subscribe