Begin by gathering all the necessary ingredients.
In a multi-functional pressure cooker, such as an Instant Pot, combine the water, beer, and minced garlic.
Insert the trivet into the pot, then place the brisket atop the trivet. Sprinkle the spice packet evenly over the brisket. Secure the lid in place. Select the high-pressure setting according to the manufacturer's instructions and set the timer for 90 minutes, allowing approximately 10 minutes for pressure to build.
After the cooking time has elapsed, carefully release the pressure using the quick-release method as directed by the manufacturer, which typically takes around 5 minutes. Once safe, unlock and remove the lid.
Carefully transfer the brisket to a baking sheet, covering it with aluminum foil. Let it rest for 10 to 15 minutes before slicing.
Serve hot and enjoy the delightful flavors of your meal!