Will not start and leaking some type of liquid?

So, recently I had gotten my car worked on and the only two issues I was having at the time were the catalytic converter and carbon build up. Recently I’ve started having an issue with my car starting. It’ll make a noise like it’s trying to start or building up to start but won’t fully turn over unless I press the gas a few times. Today I tried to do the same thing and it wouldn’t start at all. I also seen today that it has a liquid that is leaking out of what I believe is the oil pan under the engine. This is my first car and I’m not sure what to do with it. I’ve had a lot replaced already and like I said I’ve had it worked on a few times within the past 4 months. Another thing is also recently since I’ve had to press the gas to get the car to start when it finally does turn over the car has a gasoline type smell coming through the air vent into the car and it only smells when you start the car after that it doesn’t have the smell.