Assuming you have a garage door sensor that works as an IFTTT trigger (the "this" part of IFTTT), you can use the Virtual Buttons skill and its IFTTT service to trigger an Alexa Routine (the "that" part of IFTTT). The Alexa Routine can have Alexa say "your garage door just opened."

You have to create a free Patreon account to enable the Virtual Buttons skill, but you do not have to join a membership tier to use the skill (unless you want more than one button).

You can use the Virtual Buttons skill. It's easier to setup than going through setting up a developer account with Samsung.

It has subscription options, but only if you use more than one button (the first button is free).

Both Home Assistant and Alexa skills like Virtual Buttons can trigger an Alexa routine. Both can be triggered by a webhook, and in turn can trigger the Alexa routine. Alexa routines can now include any arbitrary command that can be given to Alexa by voice command.

Issues:

Home Assistant requires its own dedicated server, and it can be complicated to set it up and keep it running. See https://github.com/custom-components/alexa_media_player/wiki for information on just one of the Alexa components for Home Assistant.

Virtual Buttons only allows one virtual button for free, and it's expensive to subscribe for more buttons. See https://www.amazon.com/Thomptronics-Virtual-Buttons/dp/B08259XK1Z and https://www.patreon.com/VirtualButtons.