Alexa and Echo and TV

Hey everyone, I’ve been trying to figure out how to get Alexa to change the TV channel for me. I’ve got an Amazon Echo Dot and a smart TV, but I’m not quite sure how to set this up. I’ve heard that some TVs have Alexa integration, but I’m not sure if mine does. I’ve tried saying things like, ‘Alexa, change the TV channel to 5,’ but nothing happens. Does anyone know if this is possible? If so, could someone walk me through the steps? I’d really appreciate it! I’m hoping to set this up so I can control my TV hands-free. Thanks in advance for any help!