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If you mean special offers, you can do this when you create a product - you just choose a date from the ‘Special To Date’ text field.
If you want something more bespoke, you’d have to decide what you want to do and write a function which disables products when they move beyond a certain time threshold. You’ll need to be more specific though.
If you need advanced functionality for limited time offers, would like to offer this FLASH / PRIVATE SALES extension which allows to run campaigns with a click. See more details on the product description page.