If his employment is at will then they can fire him anytime, regardless if he gives notice or not. Nowadays a lot of job application ask if you have quit your job because you knew you were going to get fired. Regardless, best thing to do is conserve money and look for another job and also prepare to apply for unemployment benefits. Yes you can get unemployment even if you get fired because the burden is on the employer to show that you were fired for cause and that is a high burden to meet.