Adding vertices to a plane

Guys I need to add 30 vertices on each of the two opposite sides of a rectangle of a plane in blender 2.9. I try to use subdivide but obviously I am found something wrong.
I want to use these vertices to fold my plane in a fan shape. Some one help please !

Have you tried using edge loops?

CTRL R and then use your mouse wheel to scroll until the number hits 30 in the bottom left