To journal, you don't really have to write a lot, and what you write doesn't have to be correctly spelled or grammatically correct. The goal is to just write down what ever is in your mind to try and help you understand it better.
What you write is intended for you, and not for any kind of presentation, so even if you do not like writing, or you think what you write is not good, it doesn't matter, because it is for you.
Some people who are new to journaling tend to go a little bit over the top and write whole pages, sometimes because they actually have things to write about, other times, because they think they need to keep writing and fill up a whole page or two. There is no specific amount of words or pages that you need to write to journal. Even writing something as short as "Today was a good day" can be enough to capture what you are feeling and want to write down in that moment. So don't think that you have to write a lot to make journaling work for you.