No and no. It's not too late, and just watching sitcons won't teach you enough to start speaking. But if you just start actual studying and practicing you can learn it just fine. Watching TV can be used to practice listening, but on it's own it's not enough unless you're a wonderkid.
I think ActivityPup isn't even integrated into Threads yet? On release they said soon, a week later they said it was long-time planning. Haven't heard about it since.