Help! upload file

[YinYin]

I already understood that and it doesn't answer any of my questions.

I assume the answer to my first question is: you don't.

For the second one I don't see anything preventing you from signing up on websites via your phone. But I can imagine you having trouble with uploading certain file types from your phone - someone else creating a file hosting account for you and passing you the login wouldn't help you at all if this is your issue.