How to add margins in elements
Margin settings can be found in WordPress left menu, Appearance > Customize as well as in Elementor for some elements.
Margins for Logo
1. From the WordPress left menu, go to Appearance > Customize.
2. From the customizer left dashboard, go to Header.
3. In the header popup, go to Styles tab > Logo.
4. Add your custom margin (value is in pixels).
5. Close the popup and Publish the changes.

This way you can set margins for any other section: menu, footer, title bar, etc.
Note: You can change the values with your mouse wheel, just scroll up/down to increase/decrease the value.
Margins for mobile devices only
In Customizer, there is a tool which lets you set margins for mobile devices only:

Remember: The default value may not be 0 all the times and in case you want to have no margins, you may need to set 0 manually in the value box.
Note: If you are looking for Element margins, you need to follow up the Elementor tutorial on how to set margins. Also, pay attention to the Section’s margins.
Margins between elements
If you added elements to your content into columns, you can add margins between columns this way:
1. Go to Pages and open a page to edit.
2. Click on Edit with Elementor button.
3. Click on the Edit icon in the column.
4. Go to Advanced tab and click on the Link icon to unlink values together, then set margin values.
5. Click on Update button.

Note: To find information about padding settings, refer to this article and read Adding borders article to learn how to add borders around the elements.