Some of these devices like firestick etc let you run a "cast" app which lets you cast content from your phone to your tv.
I have firesticks connected to all my TVs. It's great because you can install apps and get all sorts of free content and can also use YouTube, netflix etc. These days there is always new stuff being released for these sorts of devices.
I'll second the Amazon Firestick. I use it for all of my TVs. They're pretty inexpensive too, I think $30 or so. You'll need a TV that has at least one HDMI connection.
No worries, it's amazing the amount of stuff these devices can do and all the apps you can get that provide content. If you search for firestick apps on YouTube and start to watch them you might run out of time to visit us at Bitog!