In Word, you can certainly make use of Building Blocks to quickly insert not only blocks of text, but also text boxes, pictures, and other objects. But it won't be as flexible as you are hoping for, I'm afraid. For example, if you want headers and footers to be inserted along with these objects, you'll have to add a section break to your Building Block. This is going to be difficult to maintain.

Frankly, what you are trying to do is a task for a page layout program rather than for Word.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional