I’m a native German and English speaker and I am learning French at the moment. Started in school a long time ago, but after a long hiatus, have only recently become serious about it.
What worked (works) best for me is:
Vocabulary first, starting with nouns. Learning the French words for everything closest to me gave me already a good feeling for the language. Before long, I wanted to learn verbs and adjectives.
Short sentences. Along the way, I learned short sentences. Doing that, I couldn’t help but learn something about the structure of sentences and some grammar, too.
I took some time before I learned grammar and I only started doing so when I felt I wanted to do it. I want this to be a fun experience, not a chore. And only once I felt a certain urge to put up with grammar, I looked deeper into it.
What helped me tremendously in starting off this journey was getting me a dictionary / tourist guide with all the basic vocabulary recommended. This dictionary has vocab and senctences by topic, so I could start in a field that interests me (again: fun factor).
Almost forgot: I read and talk out loud. In the beginning, I didn’t watch TV or YT-videos in French. Well, that’s not quite correct: When I did, I was shocked by how little I understood! But the more vocab I got under my belt, the more I started to understand and now I watch French videos again. Even though I have to rewind some parts again and again, it feels good and teaches me a lot.
I also hear Chansons from the 60s, 70s and later. I sense that French music is much different to German or English music and brings me the French culture nearer. It’s fun to hum along to a French tune, too, even with all the tongue twisters 
I have recently started to read my first novel in French and feel immensely enriched! (mind you, I still have to look up a lot of words and sometimes have to think hard about the meaning of the sentence. But as long as I find pleasure in doing it, I will keep on).
Hope this helps and wish you a lot of success!