I'm a teenager and want to film some stuff with my friends and edit it to look cool, shall I use a camcorder or dslr?

What do you have acces to ? Your camera, composition, lighting, editing, story telling skills are MUCH MORE IMPORTANT than which camera you use.

Good luck. Have fun.

DSLR's are photograph cameras with some video features added in. Unless you are an experienced photographer with a SLR and understand depth-of-field, ISO, shutter speed, etc., a DSLR is a learning curve that might drive you nuts.

A camcorder is designed to shoot video and just does it better and simpler.

Example: Many DSLR's have an auto focus feature. You slightly depress the button and the camera moves the mirror and samples the image and decides how to focus. But if the subject moves forward/backwards for video, the DSLR sometimes has trouble adjusting focus quickly & the motor noise usually is audible on the recording.

A camcorder responds to changes in focus a lot faster and a lot quieter.

This is just one of many examples why the proper tool for video is a camcorder.

Camcorder. Maybe an action cam.