Whether it's adding Google Analytics or any other custom function like the comments section, you can do it using the Code Injection feature.
1 Login and open the Blog page editor. Click on the settings icon at the top right.
2 In the sidebar that opens, there is a 'Code Injection' section at the bottom.
Add your script in the input box below the Code injection.
3 In the dropdown, you can select where the code has to be injected. There are different options, like on all article pages or only on the main blog page, header/footer/sidebar, etc. Choose the option that matches your requirement and click on the "Save Code" button.