Greetings from Mikey at Just Answer!
I'm sorry I can't tell you where your fuel leak is from where I am sitting but I can tell you what you need to do. There is a tool that most mechanics have today called an evap leak tester. This tool is also called a smoke machine. The tool is attached to the fuel tank vent system and pumps in pressurized smoke which can then be seen with a bright light.
This smoke machine method of finding leaks in the fuel system usually works.
We have seen leaks in the fuel filler neck from rust, the tube where the fuel travels from your gas cap down to the tank. Also popular is leaks at the fuel pump seal on the top of the gas tank.
You can also check your car's computer for evap system fault codes, this is another indication of a fuel tank system pressure leak.
My shop charges 150 dollars for a smoke machine leak test.