As long as it fits you should be able to use it. I recently went from an old device to a much newer one. The sim was even smaller on the new one, but luckily my sim had a smaller one that just pops out of the middle of the larger one and it works just fine.
If it is an old SIM that has been inactive then no you can't reactivate them, once they are used then superseded by a new SIM on that line then they are no longer usable.
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