When using iTerm2, if you’re editing a file with vim and want to jump to a specific location in the file using a mouse click, just hold down the [Option] key when you do a normal left mouse click. That will take you to the location directly under the mouse cursor. (Unless the mouse cursor is beyond the end of the line. In that case the text cursor will be moved to the end of that line.)
I mention vim here because I just learned about this when using vim, but you should be able to use this with any app when using iTerm2. This is an iTerm2 feature (not a vim feature).