What can you do with a Nikon D40?

Like what effects are there to use and what can you do to a picture on the camera itself, what can you do on it?

No preset effects are on the camera if that's what you're talking about. Everything you can do with the camera depends on you, the photographer, and your knowledge of aperture, shutter speed, and ISO.

T. Le Mark II is right.
With the D40 you have left the realm of P&S cameras and it is up to you to get the best photo you can buy using your photographic skills and then if you want to manipulate the images, use a program like Photoshop to retouch or do any post production if you want.
If you are asking how to produce light graffiti, use selective focus or freeze action, THAT is something ANY dSLR camera can do. All it takes is for the user to learn how to use their camera using fundamental photographic skills. Those are best obtained by attending photo classes.
- On my Nikon D3400 when you try to take a video, a little mic with a line goes through it and when you get the finished product of you?
- Can you use a Nikon D40 for stop motion?
- Can you charge your Nikon D3000 in the computer, or do you need the charger?
- Can you use a Sigma lens Canon mount on a Nikon body if you use an adapter?
- Can you fix a dslr lens that makes noise (sound) when you zoom?