First, create a regular webpage and design the part you want to use as a template. Then save the file as a template (update links: "yes").
Click on the main body of the original webpage (the non-template part), and select: Common => Insert Editable Region, and name it (starting with an English letter).
Click on this editable region and go to the code panel. Place the "editable region" code outside of the `` and `` tags. (At this point, in the design panel, you will see that the cell border is blue.)
*At this moment, a folder called 'Templates' will appear in the site root directory.
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If you're just starting to learn web design, it's still best to imitate others' websites at the beginning. I recommend a great collection of websites~ There are many templates there that you can use when you start out. By imitating more, you'll gradually develop your own style.
I recently found a material website that is pretty good. http://www.72sc.com. It has a lot of BLOG materials.