If one is doing this as a hobby, I would suggest the equipment is simple and basic.
1) A good pair of binoculars.
2) Good weather-appropriate clothing including a sturdy pair of walking shoes.
3) A notebook and pen for making notes on things like - what you saw; where you saw it; thoughts on a particular birdwatching location; etc.
4) A reliable compass in case you become lost.
5) A good camera in case pictures are wanted.
6) A good friend who knows where you are in case an emergency happens and you are late returning.