Yes, of course.
Obviously it needs protection from foul odour in the form of a trap.
ANS 2 - YES, it can - but what was it plumbed into before?
The drain outlet in a kitchen sink is typically located at the bottom of the sink basin, near the back of the sink.
The dishwasher outlet is typically located under the kitchen sink, near the plumbing connections.
The nearest outlet for the dishwasher in the kitchen is typically located under the sink or behind the dishwasher itself.
An electrical outlet can not be placed behind a sink. If the outlet is witin 6 feet of a sink it must be GFI protected.
Dishwasher line is hot water. Tie ice maker into 1/2 inch cold line going to kitchen sink.
If it's an outlet that's round with many holes it is probably the drain in the sink.
2 ft would be the maximum.
Most new installations in new homes will have this feature. It is for a "garburator" which is connected to the kitchen sink outlet. There is usually a switch mounted on the wall near the sink for switching it on and off. The switch is usually mounted in a two gang junction box. The other device in the junction box is an electrical receptacle.
They're usually piped together using either a middle or end outlet fitting, into a trap, and piped to drain line under sink.
How big is the kitchen sink
It depends on sink. Kitchen sink is a very generic term, not all kitchen sinks have the same size,
Yes, you can install a single sink instead of a double sink in your kitchen.