Have a look at your fuses. If not that could be the blower itself, relay or resistor.
Previous answer is correct, you can start by jumpering 12v directly to blower to see if it works. Assuming it does, then find the fuse. Brian suggest the resistor.......if your car has an A/C that you set a temp number, it will not have a resistor but will have a blower control module. Attached picture is a Riviera but yours could be similar, the module is item #1
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