Our Flex theme is our only Shopify theme that includes built-in settings to adjust the margins/spacing between elements.
Check out our blog post to learn more about Flex's versatile spacing and width settings
For the rest of our themes, while there is currently no built-in setting to adjust the margins/spacing between elements, we do have a helpful blog post that goes over how to use the built-in developer tools in Google Chrome and what to target CSS-wise to customize your spacing:
Customizing spacing between elements in Shopify themes
If you need further help with modifying the layout, we would recommend seeking the assistance of one of our recommended Shopify Experts.