Take the plunge
Unless you’re particularly organized, common household items like plungers and knife sharpeners aren’t things you accumulate until you own your own house. In apartment buildings, you’ll rely on your super to come and unblock your sink or change your lightbulb. You probably wouldn’t have any plunger at all.
Turns out, once you’ve got a place of your own, it’s not just one plunger that you need, but several. You’ll be familiar with the flange toilet plunger, but the plunger you need for the sink is a cup plunger, with a wider brim to give more contact with the plug surround. I’ll wait while you go and make a list.