According to my understanding:

• two orthogonal forces aren't related and two orthogonal vectors don't affect each other
• the force of static friction $F_s$ depends on the normal force $F_n$, so $F_s = F_n\cdot c$ ($c$ being the static friction coefficient)

If these two are correct, how can the force of static friction, determined by a force normal to the surface, be directed tangential to the surface and orthogonal to the normal force?