Soaking beans overnight or for 8 hours before cooking them is not required.
But if you do soak the beans for 8 hours or overnight it can help prevent gas build up in your stomach when eating them.
I haven't had as much gas buildup in my stomach after I started soaking the beans overnight before cooking them first.
Then I put them in the pot on the stove and then get the water boiling and then turn the heat down and let it simmer for 3 hours.
During those three hours I check the beans and stir them every 20 to 30 minutes.
Some beans may be done in 1 hour while others may need 3 hours too cook depending on how soft you like them.