Sure, Tanjiro masters Sun Breathing in the manga. It's a turning point that showcases his determination and progress. It also ties into the broader story and his quest for justice.
Tanjiro's fate in the manga is that he ultimately passed away. This event was a significant part of the story's development and had a profound impact on the other characters and the overall plot.
Tanjiro's strength in the manga is significant. He acquires new powers and techniques, and overcomes numerous powerful foes with determination and strategy.