rotary encoder disk and arduino megar32560

hello every one. can anyone help me or give me input about reading the sensor following with arduino mega … “speed and direction / angle”. i am sory before, I don’t know where to start.

OPs image

Please provide more details of the sensor as I can tell little or nothing about it from the picture

now I’m still looking for the datasheet. this is written on the description on ebay.

Have you used the search icon top/right of the page and searched for rotary encoder ?