I learn CNC code and I have a question.

I try to make 15 Degree and 0.75 (center)
My code is:

G97 M08;
G54 T S;
G0 Z2.;
X80. (How to calculate start point?)
G01 Z0.06 F0.2;
A105. X82. F0.05;

noseR is 0.4