You can have as many Roku accounts as wish, each starts with a different email address. To get Roku's that are on the old account to the new account, you need to do a factory reset of the roku to get a new link code. Only way. Go to your computer or cellphone browser and enter roku.com/link on its address bar. Never enter it into a search engine link google or bing.
Edmund Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution." If you appreciate my answer, maybe give me a Kudo.