Hi @Paras Bhatt
You may create templates then distribute them via GPO, or SharePoint Online Office Template library.
The reference:
How to deploy custamized office templates from GPO
Create an organization assets library
Then users can choose the templates to create a new file.
But if you want to set them as a default templates, you need to replace previous local global templates with them. In my opinion, this increases the risk of use, and I do not suggest you do it.
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