Responsive type sizes

I’ve inserted text onto my site but when I scale the window larger or smaller, the type size and text box stays fixed and scales up or down proportionately with the size of the window. It isn’t responsive to me changing the window size.

Is there a way to make the text responsive to the scale of the window?

Readymag does not use Responsive design, this is why your design won’t ‘update’ when resizing the window.

I believe it is no longer a general practice for most people; at least compare to a decade ago. I’m curious. Why you need to resize it? For testing layouts?