Try out your shorts: Writing short pieces
Starting out as a writer, it's worth working with shorter pieces to help hone your craft. This doesn't necessarily mean they are easier to write - telling a story in a few words is challenging - but it allows you to concentrate on carefully selecting words, editing until it hurts, and being consistent in a piece of writing. The challenge is of course telling your story in a short number of words!
Flash Fiction
Many writing competitions, e-zines and websites look for flash fiction, which is usually around 1000 words, but could be shorter
https://flashfictiononline.com/main/
I had a short piece published on this site: https://everydayfiction.com/submit-story/
There is the opportunity for people to comment on your work, which if you don't take it too seriously, can help hone your writing skills.
Letters to the editor
Most journals have a 'letters to the editor' section. Many of these carry a cash award or offer an incentive to the top letter. To write a good letter, you need to analyse the journal, and the type of material it publishes, and it's audience. This ability is invaluable when you start submitting your work to the editors. Your writing could be brilliant, but if it's not suited to the publication, it won't be accepted.
Children's books
Children's books tend to have smaller word counts, and smaller vocabularies. However, it's not an easy market to break into. Go to your local library and read a selection of children's books to see what is currently popular, and familiarise yourself with their style and content.
Poetry
Poetry practises the art of being economic with words, and using words on multiple levels. It's a great way to hone your language skills, and practice choosing words carefully. I must admit that much as I love reading poetry, it's not writing that I aspire too - it is not my metier!
Twitter challenges
Search for #sixwordstory on Twitter - they regularly post a writing prompt, and people have to respond by writing a story in six words. It's really challenging, and fun to read the responses people come up with.
I started with short stories, and have written many, with only a few published. I've enjoyed doing it, but I am thinking increasingly that I'd prefer to writing novels. As a younger writer, I was scared of the 90 000 word count for a novel, so I wrote a trashy romance to prove to myself that I could write 50 000. It worked, because I'm no longer afraid of word counts. Now I write the story, using the number of words I need to tell it well, and then look for a suitable market. Sometimes I edit it down or add detail in response to a wordcount.
As a young writer, the more styles and types of writing you try the better - you'll get to see what works for you, and what doesn't. Trying to write shorter pieces gives you a bite sized way to tackle writing, but also a chance to try different types of writing, and develop your writing and editing skills.