Yes you can and here is how if you ever need to
You can register two or more Alexa-enabled devices to one Amazon account. Once you do that, you must put them all on the same Wi-Fi network, and then you can get them set up for multi-room music using the Alexa app, which includes creating a group for them.
When ready, update and open the Amazon Alexa app on your mobile device, and then follow these steps:
Select Devices in the bottom left corner
Tap the + in the top right corner
Tap on Set Up Multi-Room Music, then "Continue"
Pick a name for your group or select one from the list. Tap Next
On the next page select the Echo devices to include in the group. Those unavailable will be greyed out. Tap save
Alexa will connect the devices creating the group
Once enabled, say: "Play [song or artist] on [Echo devices' group name]"