Layoff notice, what does the 60 days mean? after 3 years as a mechanic

My employer announced that the site will close and gave us written notice. This is my first time dealing with any of this. Some colleagues are already leaving. Should I stay for the bonus?

Keep everything in writing and save the confirmation numbers. It made the follow-up calls so much easier.

I stayed for the retention bonus and looked for work on the side. It cushioned the gap.