Drove car when I came home it smelled like burning slightly?

So, I drove my car to run errands I was at a consistent speed of 30-35. I got home, parked my car and lifted the hood to see how the battery hold down was doing because it was new and I wanted to make sure it was fine. When I did that I noticed a slight burning smell. Now I have all my fluids in the vehicle and it got an oil change a few months ago and yesterday was the first time it's been driven in months. I'm not sure if there are any leaks, the exhaust side looked clean but the engine bay itself is dirty. It hasn't been cleaned up since the last owner. I did notice that my fan in front if the radiator more than likely wasn't turning on but I also did not glance at the temperature gauge either I am afraid to take it on a drive to check if it spikes or not and I did not want to let it idle to see if it kicks on just in case I make a bigger problem. So, what should I do?