Hit the Sign in tab and configure your login data.
Select and play the title you want.
Right-click anywhere on your PC screen and choose the Cast menu.
Choose your Chromecast device and click the Cast tab option displayed under the Sources.
Now, the PC screen will be cast to the TV. The title you played on Tubi will appear on the TV screen.
Tubi is a completely free service and it is one of the best alternatives to costly streaming services like Netflix. Moreover, you can directly install Tubi on major streaming devices such as Firestick, Apple TV, and more.