Having a support system is one of the hardest parts of being a writer. I think you are passionate about writing (why else would you be on Medium?), so you will never really run out of ideas. You will have good days and bad days, creative days and “blank” days, though, and that’s part of the process. As for your English, I can relate. I am fairly fluent when speaking/reading/understanding Spanish, but have a harder time writing it (damn accent marks). There are many free online courses that you can take if you want to improve your English writing skills. Harvard, offers lots of their classes online. I’ve taken a few writing courses and recommend you do too if you have the time. Also, you should read as much as possible. You will pick up many things from that. You have everything you need to succeed at your fingertips.
Thanks for reading. Wish you the best.