Bring out the popcorn and start watching some Power BI movies. Although not exactly blockbusters, they are a great place to get started with Power BI.
With over 300 videos and nearly 30.000 subscribers, the place to go. Especially good if you are just getting started with Power BI, as it also contains the videos for the complete edX course Analyze and Visualize Data with Microsoft Power BI (all 132 videos here) and the Guided Learn material (also see the Courses Page).
Guy in a Cube has 200+ videos and 4000+ subscribers. Short videos with news and detailed explanation of specific features.
If you insist on learning Portuguese and Power BI at the same time, or your native language is Portuguese to start with, Planilheiros is the place to go. It has some 170 videos and over 15.000 subscribers.
The only non-YouTube channel on this page. It has over 250 Power BI videos in multiple languages. Some very cool demos, some more broad sessions where Power BI is one of the topics discussed.