It is absolutely possible. I currently have three Chromecast devices (and a bunch of smart speakers and even some old Chromecast Audios) on my network.
Just go through the setup like normal for each Chromecast. It helps if you plug in and setup one device at a time if you are trying to setup multiple ones. Give each one a unique name when asked. Names like Living Room TV, Den TV, etc so you can tell them apart.
