There is only one port on the Chromecast with Google TV, which is a shame because it is a great little streaming box. If you want to add more storage to the internal 8GB or if you want to add more speed to the internet, you will need to get a hub with a lot of ports and pass-through charging.
I would love to let you know that you can plug your Chromebook's hub into your TV with the help of the internet. Our favorite hub is the Aukey LinkPD Pro. The reality is that not every hub is compatible, and that compatibility is also impacted by what you use to power your setup.
It was shipped with a power brick rather than a power delivery device because it was cheaper to do so. The brick is powerful enough to run the Chromecast, but it doesn't have enough leftover power to power most hubs. Since the charging tech it uses isn't Power Delivery, most hubs don't recognize the full power and don't pass it along properly. The Vemont Premium 5-in-1 Type-C Hub, which has been tested by multiple users in r/Chromecast over the last few months, is your best bet if you need a hub that works with the in-box power supply.
If you are going to use a USB-C hub with your Chromecast with Google TV, you need more power, so please grab either a 65W Power Delivery Charger or a 90W Power Delivery Charger so that you ensure that. I use a 45W charge with my device, and it has not caused me any problems yet.