Latency refers to the amount of time it takes to get information from point A to point B
"Speed" is usually referring to "Bandwidth" which means how much data can you send at a time.
Satellite connections have high latency because of the greater distance that communication has to go.
For example: Communication has to go from your computer to a satellite, from the satellite to a server, from the server to the satellite, then finally from the satellite to your computer.
Communications satellites are generally around 22,000 miles away from earth, so the simplest communication has to travel more than 88,000 miles to get back to you.
Wired network connections don't have to travel so far to get information back and forth to you. big companies like google have 8 data centers in the US alone, so your information is likely only traveling about 4,000-10,000 miles total.
Bandwidth just refers to how much information you can send at a time, and it doesn't take processing time or transmission distance into account.
I hope this helps clear up some things and doesn't confuse you even more. lol.