Many students and researchers feel they don’t know how to write their thesis or journal manuscript, but please don’t be discouraged. Professional sports players spend years training. Brilliant artists aren’t born with the ability to draw and paint.
Just like any other skill, it takes lots of time and effort and become an effective scientific writer. If you think about writing as a learning process, then you can become better by allowing yourself to make mistakes, asking for help and critical feedback, and learning from others.