Just a random tip: something that helped me a lot was learning about the IPA for pronunciation help.
You don't have to learn the whole thing, just the symbols and sounds that make up french phonology. The following pages might be helpful:
Most dictionaries will give the pronounciation of words in the IPA, and I've
found this invaluable for learning how different words are pronounced.
Hope this helps! :)
Focus on pronounciation is a good thing, because I able to understand someone who speak french with a lot of grammar mistakes but it will be difficult if "un" [œ̃], "on" [ɔ̃],"an"[ɑ̃] or "u" [y], "ou" [u] sound the same.
Some people are afraid by french grammar (especially conjugaison) but you don't need at all to know all the grammar to start speaking french.
Some tenses (présent, futur simple, passé composé et imparfait), accord feminin/masculin and singular/plurial for adjective, some articles and you're ready to speak.
Last but not least, listen "true" french on TV, radio... We don't speak french as we write it, sometimes we cut words or add little sound (liaison) between words. It is not complicate but it could be quite confusing at the beginning.
First, of course if you want to sound french it is better to have the french "r" but it is not a obligation. Any "r" from the back or from the front (like russian or spanish) will do the work.
The big french "r" looks like a small "gargle" but without water ^^ And the small one, more likes a throat clearing. It is normal to have sore throat at the beginning but when your throat is sore, just take a break. French don't hurt themselves when they speak ;)
To dedramatise, Vladimir Fédorovski speak french, write book in french,he is often invited on TV or radio but he still using russian "r" : Video
Try to listen to a French radio channel. I have listened to France Bleu 107.1 for the Paris Region. They play French as well as international music. There are news, quisses, cooking and other topics. I understand that its very hard in the beginning to even understand singel words but if you give it try you will see that you slowly will understand more and more. I use TuneIn Android app to listen with my mobile. Nowadays i listen to Europe1 as well were they talk more frequently.