I am putting in my e-mail to sign up with roku but telling me wrong e-mail
Then you must be at the login screen, which only works if you have already created an account. There is probably a button or link to "sign up" or "register"... you should click that.
Well, did you make sure that you put it in right or did you press more than one button at the same time next time write it down on a piece of paper
It may be because you are putting it in on the login page. Look for where it is written "Sign Up" and then click on there. Fill in the empty spaces with the details needed, and then follow the instructions given, so as to complete the process.