[Theme – Tesseract] How to edit the margins for all my pages to have more space

Hi all,

my website is https://www.quinnaccountants.com

I would like to edit my page such that I can use more of the “white spaces” to the left and right of my pages.

Currently when i paste my images (using pagebuilder), there is a lot of wastage empty white spaces I cant use.

How can I change this? please help.

thank you.