"You only learn to be a better writer by actually writing." Doris Lessing
Novelist, Doris Lessing. said a mouthful in the quote above. Her short declaration is filled with good advice. It may sound a bit ludicrous to some, but believe me, there are many writers who fill their lives with writing tools, books, and writer friends but who do very little writing. They are in love with the idea of writing.
I was once in a small writer's critique group that asked the members to bring something new to read at each bi-weekly meeting. The others would discuss each offering giving praise for the good parts and suggestions to help the weaker areas. We spent a good deal of time at the beginning of each meeting talking over any news from the literary world, sharing markets, and general chit-chat about writing. Sounds like a good group, doesn't it?
I'm afraid it turned out to be a group where one or two people read their work and the others did give weak critiques but they wanted to spend more time talking about writing. They wanted to be a part of the writing world without that one essential ingredient--writing!
As the group leader, I begged people to bring samples of their work and to read what they brought. I tried to bring something to read to each meeting. Finally, it was me reading and them discussing my work. At that point, I gave them a choice--either participate or we disband. They chose the latter and later remarked to me how much they missed the group. They didn't miss writing. It was being a part of the writing world and talking about the writing world that interested them more.
Sadly, none of those people were going to become better writers. Ms. Lessing was correct in advising that we must actually write in order to become a better writer. A pro baseball player does not become a better hitter by talking about it to the other players. He does it by hitting a ball over and over and over again to improve his ability.
If you're stuck for an idea on what to write, do an exercise. Try a Random Word or a Picture Prompt. Google Writing Exercise to find others. But write something every day.