Monkey D. Luffy is the protagonist of Eiichiro Oda's One Piece, and he set out to sea with the aim of becoming the Pirate King. While Luffy was a born genius at fighting, he was, expectedly, nowhere near the level of the strongest characters in the story. Luffy's fights against the likes of Aokiji made him realize how big the gap between him and the elites of the One Piece world was. Shortly after, the crew was destroyed at Sabaody Archipelago with Luffy being unable to stop it and all that was followed by the death of his brother, Portgas D. Ace, who Luffy failed to save.
Ace's death became a gateway for Luffy to grow stronger under the tutelage of Silvers Rayleigh, the former right-hand man of the Pirate King. Just like the rest of his crew, Luffy spent two years training his abilities to the fullest. After the timeskip, Luffy has continued to grow stronger in the New World by fighting against strong foes such as the likes of Katakuri, and even the Yonko Kaido. In Wano, Luffy has progressed as a fighter by leaps and bounds and finally established himself as one of the strongest pirates in the whole world, meaning he is potentially close to Yonko level.
One Piece: Ways Luffy Is Just Like Gol D. Roger
The Yonko are easily the four strongest pirates in the world of One Piece who rule the second half of the Grand Line, called the New World, like kings. Until recently, even the Navy didn't dare to interfere too much into their doings in the New World, however, under Sakazuki's leadership, they're openly challenging the Yonko in the seas. Before the timeskip, their ranks were made up of Whitebeard, Big Mom, Shanks, and Kaido. Whitebeard's death during the Paramount War led to him being ultimately replaced by none other than
Read more on gamerant.com