cc - why did you say you were going to tell us how you did it but you didn't.
He didn't. He said
What he generated, not how he did it.
In fact, the OP would likely do better with a frame, Because LibreOffice have this to say
How do I change the default font for Text Box in Writer? I can change on a case-by-case basis using Properties, but I want to have my default template always apply my preferred font to new text boxes.
You can’t. It is a common mistake to use text boxes for what should be text frames. Text boxes are graphic objects beyond the reach of the Writer formatting machinery. They are external to text because they are just part of a drawing. Note that if these graphics are created with Draw, you have sty…
You can insert a Frame by using from your Writer menu
and start working with that.
While the frame is being built, you can right click in it and choose Properties and as well as having all the options you need to format it you can click Help in it and it will open your default browser and load the relevant Help stored on your hard drive.
First one is a text box, 2nd one is a frame.
This one is a frame being built, and you can drag any of those 8 handles (little squares)
The above shows the Frame Properties, Area chosen, and if you click the Help button bottom left it will take you to the appropriate help, sourced from your Hard Drive.
You can see from the address bar that it is sourced from a file on your drive rather than the internet.
And you'll note it is Help for your 6.4 LO Writer.
For our Helpers if they need it - the OP is using one of the U series of Linux Mint, that is, 20.0 'Ulyana', 20.1 'Ulyssa', 20.2 'Uma', or 20.3 'Una'.
He initially post the thread in Mint, and I moved it to General Computing, since we do not officially support LO.
That also answers questions from @f33dm3bits
regarding Windows and whether his distribution was about to go EOL.
I know this because all 4 of the U series, if updated, use LO 6.4.7, with Ulyana having shipped with 6.4.2 (and since updated) and Ulyssa 6.4.6 (and since updated). The V series starting with Vanessa on 21.0 went to the 7 series of LO.
Over the years and releases of LO there have been changes made to Text Frames, and so it was important to find out what version of Mint he was using, which he failed to provide.
Further, if he had been using LO 6.0.7 he would have been on the T series of Mint (Tara, Tessa, Tina and Tricia) all of which expire 30th April.
The OP can get official help from
... although I am unsure how they will respond to his deciding what he is willing to provide or not.
Cheers all, and thanks as usual to all our valued helpers.