How do you find a vertical and asymptote of a linear function?

Answer 1

Your question contains a grammatical error, I think you are asking about a vertical asymptote.

A linear function is a straight line.

The only way a straight line can be vertical is when its slope is zero, that is , the equation must have the form
x = k, where k is a constant

For linear functions we don't speak about asymptotes.
Asympotes are lines that another line will approach but never reach, and that other line is usually a curve.
e.g.
y = 1/x approaches the x-axis as x gets larger, but the curve never gets there.