If you subscribed to Hulu you'll need to install the Hulu channel app on your Roku. Then, when you start up the Hulu channel on your Roku, click on LOG IN and follow the prompts to log in to your existing Hulu account.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you.
Streaming Stick 4K+ 3821 | Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Streaming Stick 3600
If this post solves your problem please help others find this answer by clicking "Accept as Solution.". Please only do this if it ACTUALLY solves your problem.