How to fix the position of text in a container when changing screen size?

I've added a stack and inside the stack I have a container (the background of the container is an uploaded image). Both the container and the background image are 1080 x 1350. I've added text onto the container. When I change the screen size from phone-tablet-desktop, the text will move to a different position in the container. How do I fix the text to exactly where I want it to be on the container even when resizing the screen?