Intensive Driving (crash course)?

I am english but i do not live in the the uk. However in two years time I will move back. I am 17 and going back to the Uk in the summer, and i need to learn how to drive over the summer as I can't do it locally. I think i need a crash course, and im hoping to do one in devon, near plymouth. However I am unexperienced and worried that I won't past first time with an intensive course. What shall I do? Shall i try and get some driving practice before i go back this summer and does anyone know any reliable intensive courses? I would like to possibly do the course in no more than 4 weeks.