How to add pictures onto a manga or anime someone added

What i mean is when when given the choice to add an anime or manga or whatever it may be how does one upload a cover picture for it i am on an iPad so that may be part of the reason why i cant add a picture if so can someone tell me i added two manga Seraph of the end All you need is kill

yeah it's a bit anoying i just added a new anime but i was going to fast and now it's posted but i can't change it it's kinda anoying can u make it so the persone that post's the anime/manga can change things same whit the forum when u make a spelling mistake or something u can't change what u posted i mean the topic