Mobile viewport height not responsive

I am currently building my portfolio. My desktop view is fine and I’ve gone through each page to sort out a mobile solution. However, when I open the mobile view on my phone, the viewport is stuck at what I guess is the iphone SE preview size. There are black sections at the top and bottom of the viewport, and when I scroll, the safari search bar doesn’t condense and stays the same size. This dramatically gets rid of like 1/4 of viewable sections of the site and requires more scrolling.

Does anyone know how to change the viewport height to be responsive and not fixed? My site can be viewed here: https://maryclements.online/

In safari browser: