I assume you already consume a lot of English-language media? Try doing it without Spanish subtitles, or at least, only with English subtitles. Even if you don't understand everything you can pick up a lot passively and it will help you start thinking in English. Same with books, although constantly looking up words in the dictionary is pretty tedious.

For spoken language practice there's no substitute for just living in a different country for an extended period. Since you're in Europe it seems like this might be possible for you?

Your written English already seems passable. If you hadn't mentioned you were not a native speaker I probably wouldn't have noticed.