I would recommend a Raymarine radar. I have had Raymarine on my charter boat now for 15 years. The Raymarine products have been dependable for me and the thing I really liked about them is that they are very user friendly. You don't need to be a computer wiz to run it.
With that being said no matter what unit you get, use it. Meaning in the beginning when you are getting comfortable learning the unit on days that the sun is big and bright turn it on read the book and push the buttons and learn what it can do and how to do it. See what targets look like on the screen. Both moving targets and still.
Don't wait till your out fishing one day and the fog rolls in and you can't see the bow of the boat and expect to turn it on and know what you need to do and what things look like on the screen. That is not the time to crack the book and practice. But you do need to practice, practice, practice