Yes, writing is an art! No matter the language, you only improve by practicing and reading. Especially when you need to write, read or even speak out of your native language, it is more challenging.
Fortunately, there is a plethora of online tools, free or chargeable, to help us improve our grammar in English in this instance.
The main tools I learned to use during my thesis for professional and scientific writing are:
This is a simple online dictionary that provides a lot of synonyms for words with usage examples collected from many articles worldwide.
DeepL is an online translator, for more or less long texts, based on Linguee.
Grammarly, on the other hand, does not provide any translation utility but instead helps you correct and check the grammar of your texts. It is an amazing tool, really! You should try it. I highly recommend the chargeable version, which brings a lot more powerful and interesting features for deeper delivery. Furthermore, you can integrate it with many other tools (e.g., your browser, chat tools like Slack, email tools, etc.) to have an in-core direct correction and checking without the need to copy the text to the online page. To tell you the truth, I am currently using it to write this page 😉!
To complement these tools, I try as much as possible to improve my vocabulary by:
Reading a lot of papers, articles, and books and note some words that I find particular and not vulgar in a file.
Using a synonym generator tool, for instance, Reverso. Using a variety of synonyms (to avoid using the same words over and over again) in your scientific or literary productions gives a softer and more sustained look to your work and allows you to stand out from the crowd and for those who read to enrich their vocabulary as well.
One tip I advise is to use DeepL to write your text in your native language, with your own words and sustained vocabulary, and then translate it to the being learned language, to have more chance to also get sustained words in that language.
You can find in my Word is Freedom words bank some words that I find particular and keep for my future writings. Most of those words come from the book Operating Systems: Three Easy Pieces of Arpaci-Dusseau, which I found highly well-written, easy to read, and even fascinating.
The file is opened, and everyone can contribute to it. Feel free to reach out if you are unable to access or modify it.