English is not my native language either.
Haven't heard about engvid.com, however, my advice would depend on what the current level of your English is. Anyways, reading a lot of articles on your topic of interest to enlarge your vocabulary will help in any case. You will get better idea of how written, more formal English sounds and what structure of sentences are mostly used. Also, try thinking in English, no matter what the topic is, even in everyday situations, think directly in English, without thinking in your native language first, and then translating. Everything comes with practice.
, you should not encounter any roadblocks to writing your blog post. As long as you have an adequate vocabulary in your niche, then you can write a blog like you're talking to other people, if you can tell a story and speak to other people about your niche then you can pour it into written text. Don't worry too much about grammar, currently, you can use Grammarly's free tool Chrome extension to fix your grammar error. I believe by actively reading about the blog can help you improve your vocabulary and skill to write English blog even it's not your native language, the same case as me 
