I highly recommend just routine googling. Books (at least the ones for English speakers) are poorly written and wrong in my experience. They're written by someone who practically doesn't even speak russian and reviewed by a native speaker who doesn't necessarily know their own language. It's like asking a native English speaker to check a book that teaches "who" and "whom", that person has no idea. 10 internet videos will teach a concept to a strong understanding while reading a book's explanation over and over might give a shaky understanding at best. No matter what happens you'll always want multiple sources explaining in multiple ways, if you do that with books, you're wasting time and money. The internet is right there, free. That's just my experience with books that try to teach Russian.