I understand this is a Libre question and not a Zorin one.
Libre calc insists on capitalizing the first word from any text I enter in a cell.
What I have tried:
I don’t have “autocorrect” anywhere under Tools. The Libre in-built Help option suggests the same thing.
What I do have under Tools are: Run Macro, Edit Macro, 2 Organize commands, Goal seek, solver, 3 Trace commands, 3 Remove commands, Fill mode Auto refresh, Mark invalid data, Data sources, XML settings.
I did try Options->Language settings->Writing aids and unchecked “check spelling, grammar, uppercase” options. But that didn’t work.