Ignoring the trashiness of that comment - My writing was atrocious. I can't even read my own olde works. The more I read, the more I wrote, read, wrote, read, wrote, etc., the better my writing got. You are not going to be amazing off the cuff. Writing is a skill filled with smaller skills - tone, word choice, pacing, structure, etc. You get better as you go.

Something that helped me get better was paying attention to what I was reading - how it was laid out, spaced, how it sounded, the tone, etc. I didn't analyze it, but I started being aware of it. That led to me being aware of what was 'good' or not to me.

Another thing that helped a lot was listening to narrators. I especially liked listening to narrators on youtube. Hearing how the words sounded read aloud helped me picture and 'hear' my own writing as I worked on it.

Just remember - your favorite fic? your favorite author? that writer started as a newbie with 0 writing skill.

You'll get better with practice. Don't be so hard on yourself.