Newbie needing some help

Hello everyone. Thanks in advance for help.

I am a complete newbie and trying to learn here. I have a computer and networking background but recently started tinkering with a 3d printer and making small electronics for my RC hobby.

I am making a winch controller. So far I am using 2 relays and a ATTINY85 chip to make a servo motor scroll in and out for a winch. That part was easy(ish).

Now I need a way to regular the voltage to the chip. the chip is designed for 5.5v and I have anywhere from 5 to 9v coming in. I need a way to regular that voltage to 5.5v. I am not sure how to do that.

Thanks

Regulator