replace old macbook pro 2014

1. Not much, but there are many factors involved in determining its value. Estimate its value by perusing sold listings for similarly configured Macs on auction sites. You will get more by selling it yourself vs. an auction site. Be sure to follow these instructions: What to do before you sell, give away, or trade in your Mac - Apple Support. They are not optional (unless specified) and must be followed to the letter.
2. The latest release of anything will enjoy the greatest economic life. If you are asking about the M1 vs. M2, the M2 is the more recent of the two. The M2 Pro and M2 Max are the latest versions, and the M2 Max is the more capable of the two: MacBook Pro 14-inch and MacBook Pro 16-inch - Apple

omits wrote:

Thanks. I'm looking for a new 13".

FYI, the 13" MacBook Pros are more like the 13" MacBook Airs than like their 14" and 16" MacBook Pro cousins.

The 13 M2 MacBook Airs and the 13" M2 MacBook Pros have

• • 8, 16, or 24 GB of RAM (non-expandable)
  • Two multi-purpose USB-C (USB, DisplayPort, Thunderbolt) ports
  • WiFi, Bluetooth, and a headphone jack (but no memory card slot)
  • The ability to drive at most one external display

The 13" M2 MacBook Pro has a Touch Bar (small touch-screen panel) in place of a row of function keys.

The 13" M2 MacBook Air has a MagSafe 3 charging port that the 13" M2 MacBook Pro lacks. (You can charge the Air through MagSafe 3 or through USB-C.) It has a better Webcam (1080p) and weighs less (Air: 2.7 pounds; MBP: 3.0 pounds).

You can do a more detailed comparison of the 13" M2 MacBook Air and 13" M2 MacBook Pro using this page:

Mac - Compare Models - Apple

Yes. When you set up the new Mac, the setup assistant will ask if you want to transfer content from the older one's Time Machine backup.