Hi Dipak, hope you are doing well,

Let the forces be F1 and F2
F1^2 + F2^2 = 90 N
(as the angle between them is 90° or right angle)
when angle is 60°
F1^2 + F2^2 + 2 * F1 * F2 *cos(60)=117 N
90 + F1 * F2=117

F1 * F2 = 27
(F1 + F2)^2 = F1^2 + F2^2 + 2 * F1 * F2 = 90+27×2=144
F1 + F2 = 12..............(i)
F1 - F2 = √( ( F1 + F2)^2 - 4F1 * F2) = √36 = 6.........(ii)
from eq.(i) and (ii) We get....
F1 = 9 N ,and F2 = 3 N

Feel free to ask doubts in the Comment Section like this.

I hope this helps you.

Thanking you

Yours sincerely

Somenath Chattopadhyay