How do I get rid of the space about page title?

In my child theme I deleted the site title and tagline. How do I get rid of the blank space where these would’ve appeared?

You can do it by targeting that particular element class using CSS.

.your-awesome-class-name {
display: none;
}

Just add your own class for element you would like to hide. You can use Google DevTools to inspect these elements. It can be applied to multiple elements without problems.