This is a question I am asked regularly by other language students.
Modern foreign languages at A Level are not easy and shouldn't be picked just because you aren't sure what else to study. That being said, they are extremely good fun to study and highly viewed by Unviersities and employers. My advice would be to focus, and work hard at GCSE and if you're up for the challenge and willing to dedicate time to practice then definitely take the subject at A Level.
A Level language is a lot less repeating sentences to a teacher, and more open discussions about History, Politics and opinions! Its difficult, its a lot of work, but it is great fun!