The best advice for people that want to learn how to write, or who just simply want to improve their writing skills, is to write a couple of lines each and every day. It doesn't have to be a novel, not even a short story. All that is required are a couple lines, well edited.
Here are a couple of suggestions, what you could write about.
Write about getting up, washing the dishes, brushing your teeth, or what ever other regular activity you go trough in your daily routine. This might sound too trivial to some, but once you sit down to do so, you should recognize its subtle challenges.
If you find the above suggestions to be boring, write about something that happened outside of your daily routine. A meeting, random encounter, or the unexpected visitor that popped by.
Even if you lead the most boring life, unless you're dead, there is always something happening.
Take a good look around you, and what ever catches your view, write about it. This could be a table lamp, your desktop computer, or even the monitor you are currently staring at. You can describe it, write about its purpose and function, or your personal attachment to it.
Allow me a couple of lines as example.
I spend hours looking at you. Daily. And still, I don't see you. Not that you are invisible. But it seems so in my perception, guided by my daily stare.
If for some reason you should disappear, my world would seem to crumble. And still, I find it hard to recognize your importance. I know of your value. I'm just not conscious about it. Just as you aren't conscious about your and my existence. So, no reason to feel guilty?
Another alternative is to jot down the problems you are having with writing. Express the difficulty of finding words, or forming a sentence. Now if that doesn't get you started, you may want to consider taking up another activity.