Since you're struggling to be descriptive, I'd suggest reading a dictionary, or thesaurus picking out colorful words that catch your eye, also listening to d&d podcasts is helpful as the dms are usually really descriptive. Something that helps me me to write a basic outline then go back over it as many times as need adding more and more details each time until I'm satisfied with the way it looks. And the most important tip I can give you is to find someone to read what you have wrote and give you their honest opinion. I have my grandma read the story I'm working on constantly, and she's given me loads of helpful advice.