How to fill a combobox only once

I have a combobox on the spreadsheet itself, not a userform, and I've looked through the ways of filling it and they can all be called multiple times, so after the user using the form for a short period of time the combobox has filled itself with the same options again and again
Is there a way to make it fill it when the spreadsheet initializes or only on the first click.
Thanks

Thanks for the help;

So the combobox has a list of the names of hidden sheets, and when the user presses "Go" I want it to take them to whatever sheet they've selected in the combobox

Is this possible

Thanks

Is there a way to make it navigate to hidden worksheets?
Or maybe unhide it for a short while while it navigates then to hide it again?
Any alternative solicitations will be appreciated

Thanks

I modified it to this

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and it opens the sheet, and then forces me out of it when it closes it...
is there a way to make it hide it again when the user goes to a different sheet?