paramount plus app via spectrum not working on roku stick. No where to sign in? Please help

I have  free paramount plus via spectrum . But because I have an old tv, I had to buy roku stick.  So bought roku stick and now there are only 2 (paying options to sign in.  I just want a plain old sign in to paramount plus app.   Is there a work around on this.  NO ONE HAS BEEN ABLE TO HELP ME, ON SPECTRUM, ROKU, PARAMOUNT PLUS.