Creating a Google site is a simple affair but there is loads of help available from Google when you have a query. https://goo.gl/43eZvy

Here are some links to the various tips from Google Support:

• Getting started
• Creating a site
• Site templates
• Creating pages
• Page templates
• Different page types
• See what admins can do with templates
• Adding templates to the gallery
• Page level permissions
• Site permissions
• Page hierarchy
• Inserting media and other gadgets
• Adding Images
• Embedding calendars
• Adding comments and attachments
• Changing how your site looks

Tips from others
Jennifer O’Hagan’s step-by-step written tips with links  https://goo.gl/iaA3Gm

Step-by-step Video tutorials by  Nicole Dalesio https://goo.gl/Ryly0i 

Molly Shroeder’s tips https://goo.gl/tmCzvn