If you have the valid driving license from you country, then you can take minimum 12 classes from any driving school, but you have only 2 try to pass the test,

the sessions are :

12 days classes : 900 QR approx (2 chance to pass)

24 days classes : 1800 QR approx (3 chance to pass)

45 days classes (full course) : 4500 QR approx.(5 chances to pass)

for the pricing may be little up down, and chance for passing, its depend on your learning skills,

best of luck