Construct 2 was first released 9 years ago, in February 2011. Back then, Flash was still a dominant technology on the web; Microsoft's latest browser was Intern...
I can still making/selling games with C2?
Yes, you can continue to use it. We would strongly recommend moving to Construct 3 if you're able as Construct 3 is being actively developed and now has more features than Construct 2.