Getting good at French is all about practice and constant exposure to the language. On this site we have grammar exercises for everyone, ranging from beginner to intermediate to advanced.
As someone who has been studying French for many years, I can tell you that it’s better to spend one hour learning the language every day instead of spending 8 hours in one day, once a week.
If you can afford it, get a French tutor who can coach you for an hour a week. This can be very expensive, but it can also be very inexpensive if you for example just find an elderly French person who would like some company in return for speaking French to you.
Created by a man who speaks more than 8 languages fluently, Fluent in 3 Months is an incredible program to help you master French quicker than you think is possible.
Rocket French is part of the Rocket Languages learning software and is one of the best value for money educational softwares that I know of. Try it FREE for 6 days now.