Blix bikes are equipped with Kenda brand tires featuring K-Shield puncture protection technology.
For best performance and reliability, you will want to pump up your tires on a weekly basis.
Inflate the tires to a pressure within the range given on the side of the tire. 50psi is a safe all around number.
If you get a flat, replace the inner tube. Your local bike shop can help.
Replace tires when they are worn out. A tire is worn out when it has a noticeable flat strip in the middle.