MS Word uses the “normal.dot” template as the default formatting for new documents, and this can be customized.
What is the equivalent for LibreOffice Writer?
It’s a pity that the @ajlittoz’s comment wasn’t addressed, but instead @Ratslinger, @dajare, and @ajlittoz gave absolutely correct answers to a badly asked question… You didn’t try to make yourself clear to others. A good question is more than half of answer. If you even try to express everything better, you’s come across the word “template”, and could search for it in relation to LibreOffice. This would help you better than simply throwing these words as “question”.
Since @mikekaganski seems to find some value in my former comment, I restore it as a caveat for newcomers.
Please read these guidelines and edit your question (not adding to it in an “answer”) to better explain what you did that failed (or what you didn’t do) and what you expect.
Perhaps you want Changing the Default Template - LibreOffice Help
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The existing answer provides a pointer to the Help file on this, but it only takes you part way.
Create a “Default” template
This will be your “normal.dot” equivalent. As the documentation says (with one small tweak, at step 7),
- Create a document and the content and formatting styles that you want.
- Choose File - Templates - Save As Template.
- In the New Template box, type a name for the new template.
- In the dialog that appears, double-click the “My Templates” folder, and then click Save. You will then be prompted for a name; write it and click OK.
- Choose File - New - Templates.
- Double-click the “My Templates” folder.
- Right-click on the template that you created, and click Set as Default.
- Close the dialog.
Modifying the Default Template
- Choose File > Templates > Manage templates
- Right-click on the “default” template (it has a green “check mark” icon with it).
- Choose “Edit” from the drop-down options.
- Make your changes, and Save.
Now new instances of documents will have your personal choices ready-to-go.
For some good tips on editing Template files (*.ott), see this older Q&A.
@robleyd gave a link to default template customisation.
However, I would rather recommend a more versatile approach. LO Writer allows to base any document on a designated template. With this feature, you can design a template for letters, another one for technical documents, etc. Each template has its own sets of styles, so that if you change your letter lay-out and formatting it won’t impact your technical documents.
Follow the guidelines for creating a template and store it where LO Writer can find it (see Tools>Options, LibreOffice>Paths). Then whenever you need a new document based on one of your templates, Open>Templates and choose the adequate one.
You can modify your template any time. To transfer the modifications into existing documents, open them and you will be asked if you want to update the styles. Answer “Yes” and you’re done.
If this answer helped you, please accept it by clicking the check mark to the left and, karma permitting, upvote it. If this resolves your problem, close the question, that will help other people with the same question.