Can I fit 65 Tyres instead of 55?
Properly, no. A 205/65R16 sized tire has a much taller sidewall compared to a 205/55R16 tire. If you used the taller sidewall tire you would very much lessen the handing, stability and control of your vehicle.
How much taller is a 60 tire than a 55?
A 60 means the tire’s sidewall height is 60% of the width of the tire. Just 5% taller than the 55 tire in your example.
Can I use 205 55R16 at the place of 205 60r16?
Yes it will be completely fine, in fact 205/55/16 are the most common 16″ tires.