Breaks locking up after putting new roters and pads on.

Are both front wheels locking up? How does this occur? Is it right away or do you have to drive a few miles and get the brakes warmed up first?

There's two things to consider. The first is there's debris inside the calipers that is blocking the pistons from fully returning. That is not real common. The second is something is blocking the brake fluid from returning freely to the master cylinder. To identify that, when the brakes are locked, stop on a slight incline, place a block about a foot downhill from a tire, shift to neutral, then open the bleeder screws on the calipers. If that lets the brakes release, there are multiple possible causes to discuss.

Also look at the caliper mounting hardware. Most people overlook that mounting pins and surfaces must be free of dirt and rust, and they need to be lubricated with special high-temperature brake grease. This is a standard part of a professional brake job. Typically failure to lube the important points results in rapid pad wear. The rust has to be pretty bad to cause a lock-up problem.

Did you read my reply? Is this a front or rear wheel? How difficult was it to slide the calipers over the rotors with the new pads? That should tell you if the pads are tight and holding the rotors from turning freely or if the calipers are rubbing on the wheels. With the calipers installed, can you turn the rotors by hand before the wheels are installed?

I've already missed with caliper mounting bolts resulting in the caliper sitting up too high and rubbing on the wheel. That can be identified by the wheel becoming harder and harder to turn as you slowly tighten the lug nuts. You'll start to hear the wheel rub on the caliper, and you'll find shiny rub marks inside the wheel. I've done that more than once.