I was getting ready to go to taco bell so I got in my car and turned the key to start it. It didn't start. I wasn't worried though its cold outside and the car had a few inches of snow on it. So I turned it again and I hear I loud bang noise. So I stop trying to start the car. I try again in a few min and the car starts but is now super loud. It idles very loud. I haven't moved it out of park in fear the car is going to fall apart (lol). However, smoke is coming from underneath the car from this thing that looks like a muffler but its in the middle/near the front of the car. I don't know cars well but is it possibly the catalytic converter? I remember hearing a car that didn't have a catalytic converter and it sounds the same in my opinion. But is it possible for it to smoke?

Now yesterday I was heading to a place and this lady was directing me where to go with her hands, well she kind of screwed up and had me go over a parking lot divider that I couldn't see because of snow. It couldn't have been higher than a few inches but it did scrape something. There was no smoke that day (that I noticed).

Im afraid to drive it so I don't no how I can get it to the mechanic

If it really was your catalytic converter that was hit, more than likely the thing is clogged due to being flattened. Would suggest you have it towed before you try and start it again and have a good, trusted mechanic look at it. If the catalytic converter becomes clogged it can have dire consequences for your engine's life or no life I should say.

You need to invest in one of those auto fixit books so you know what you're talking about when it comes time to have your car fixed so you won't get "taken" at a naughty repair shop that likes to soak people who don't know what's really wrong with their car. It will be the best several hours' reading that you will do, I guarantee it. I don't mean that you should fix your car, but that you should know what parts are on your car and what problems they can have, etc.