Can someone explain to me the language thing?
I'll give it a bash.
So, there's a few Japanese words you need to remember
Habu=snake
Tokage=lizard
Habu minato=Snake port
Hato= wharf
Habu and Tokage are ports in Wano.
So, the original picture was of a snake. That meant Habu Port was the gathering point.
Yasuie added two lines to the picture, which Kin'emon thought represented legs. That would have turned the picture into a lizard, making Tokage Port the new gathering point.
Kin'emon was wrong though. The two lines meant they were meant to cut out the belly of the snake. So, the sentence
Habu Mina
to (Snake Port) gets cut down to Hato. Which means wharf. So instead of gathering at Hato Port, they were meant to gather at Hato Wharf.