When will the F-35 be flown in combat?

The F-35B reached initial operational capability (IOC) with the U.S. Marine Corps in July 2015. Based on the current F-35 services schedule, the F-35A will reach the initial operational capability (IOC) in July 2016, and the F-35C will reach the IOC milestone by February 2018.

How many aircraft will each nation buy? How does this affect our security? How does this affect the price?

The current international partners' planned quantities are as follows: United States, 2,443; United Kingdom, 138; Italy, 90; Netherlands, 37; Turkey, 100; Australia, 100; Norway, 52; Denmark, 30; Canada, 65. Foreign military sales customers' planned quantities are Israel, 33, Japan, 42 and South Korea 40. In total, the total number of F-35s scheduled for production is more than 3,100 Joint coalitions with fleets of fully interoperable F-35s will have the capacity to operate with unimpeded collaboration, while maintaining security and air superiority.