The good news here is there is no actual age limit or requirement, anyone can earn an online income. A few notes though, if you are under your local age of majority, you probably will need permission, and probably need someone you trust to sign up for an advertising account. Basically, to learn to earn an online income, you need a desire, a passion, and you have to be able to put information into a logical, order. You need to know what your content will be about, and it helps if you are passionate and want to share your knowledge and information. You can be of almost any age, if you have something to provide for content you should be good to earn an online income.
What about knowing “how” to write? Not really needed either. Why don’t you need to know how to write correctly? You basically will develop a following of whtever you have for a writing style. If you put your content together and in a professional manner, you will attract certain readers and build a following. If you don’t know as much about writing and such, you will simply develop a different following. Whatever your age and writing style, you can learn to earn an online income.
All you really need to earn an income online, is a desire and passion, with these you will develop a readership and following. There are still other things to consider, such as narrowing down your niche and developing your own content. As we have said before, if you have a content idea, your are welcome to read what others may say about the subject and take information that you can gather, but always put this in your own words please. As we said, your own words and style will develop and you will build a following.