Email Alias

I'm looking for specific help on explaining to me how to get an email alias for my iCloud account? Now please don’t try and explain the entire Set up or copy and past the link or actual paragraph from apple that informs me and the rest of the world how to do it. I’ve been trying for a couple days and i must have a setting on my phone or something thats causing me to miss over it but all i need help with is actually just getting to the initial actions bar to press on my preferences. I understand how simple this should be but ive been at this all day looking over everything from all settings across the board and no luck. Is it because i can only use an actual PC to manage my account or im i just looking over whats been right in front of me the whole time?