Setting default format, font etc in Writer

I can’t find any SPECIFIC information on how a less than expert person can do this. I tried setting up a blank document to start with and saved it, but the ORIGINAL(?) “format” still returns.
The “help” sections are too complicated and not friendly to a novice.

“saved” centered, heading keeps the cursor in the middle of the page all the way down, and does not go to the margin.

So please help me on these two issues.

Thank you

Go to Tools> Options> LO Writer, Basic Fonts (Western)

Your response to this question was “Spot On”, thank you. I had gone through the “Help” program on line and it gave me a totally different answer, that did not work (feature was not showing up). Again, thank you for your clear and concise method!

Create a new template
Define as default.
Your new documents should be using that.
Changing the Default Template - LibreOffice Help