I will use this with lasers not led. Is it harmful to use. I couldn't find a lot of info about using lasers.
Screenshot by Lightshot it is my circuit.
What do you mean by harmful? To arduino? To yourself??
If you are using tiny red laser diodes (e.g. keyes 008, 5 mW 30mA), I have those wired directly to arduino digital pins.
If you want other colors or higher power you probably need a FET and laser drivers, because these require more current.
I am using 8 digital pin with 16x little 5v 5mW lasers. Will it broke arduino or powersupply or is it harmful for us.
Well I think max current for arduino alone is 200 mA.
https://playground.arduino.cc/Main/ArduinoPinCurrentLimitations
Does google not work for you?
16x30mA is > 200
you might be able to get away with 8