We don't use "aloft" much. The dictionary says "aloft" means "in the air".
1. The plane is aloft (off the ground).
2. They held their glasses aloft in a toast.
3. When dancing, the man will often hold the woman aloft and spin a few times.
Overhead" simply means over your head or above you head in elevation.
1. On ships the ceiling is called the overhead.
2. On airplanes, your carry-on luggage can be stored in overhead bins.
3. If you live near an airport, you will likely seen planes flying overhead.