If your wifi is bad, try this

Google Chromecast is one of the best devices you can use to stream content from your phone to a TV. However, if your Wi-Fi connection is weak or spotty, you may not be able to use Chromecast.

While you can use a Chromecast without Wi-Fi if you have an Ethernet connection, not all Chromecast models offer Ethernet support, with the exception of the Chromecast Ultra.

With a Chromecast Ethernet adapter, you can plug directly into your Ethernet port, eliminating any Wi-Fi-related issues you may encounter. Other benefits of an Ethernet connection include faster network performance and smoother streaming without skipping or buffering, since you have one less high-bandwidth device on your network.