As you wrote
and
I assume you talk of 2 different computers.
Therefore your questions
I’d answer with “Nothing happened. Your font did go nowhere and should still rest on your laptop.”
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Libre Office uses the fonts installed on your computer. (It may bring a sellection itself. But, if you have a licence (if I’m remembering right Century Schoolbook was not free) you are responsible to instal l fonts you have on your laptop also on your new tower.
There is no “copy all fonts I used on other computer magically” availabe. Neither in Office suites, nor in any OS I know of.
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If you have old Type-1 fonts: The format was deprecsted by adobe and is removed step by step from software. You have to convert them yourself.