Does WordPress have a way of changing the ‘Natural’ size of uploaded images?

WordPress has built in sizes for your photos that it automatically creates when you upland an image.

You can call different ones by using

get_the_post_thumbnail( $post_id, 'thumbnail' );      // Thumbnail (Note: different to Post Thumbnail)
get_the_post_thumbnail( $post_id, 'medium' );         // Medium resolution
get_the_post_thumbnail( $post_id, 'large' );          // Large resolution
get_the_post_thumbnail( $post_id, 'full' );           // Original resolution

if those don’t fit exactly what you’re looking for you can create your own size too:

add_image_size( 'my-custom-size', 220, 180 ); // 220 pixels wide by 180 pixels tall, soft proportional crop mode

and then call it by the same as above:

get_the_post_thumbnail( $post_id, 'my-custom-size' );