Michael turned $65$ three years ago and decided to not enroll in Medicare Part B during his Initial Enrollment Period $($IEP$)$ because he was covered by his employer$$s health insurance. He is $68$ now and is retiring from his job at the end of the month. As a result, he is losing his coverage through his employer and wants to enroll in Part B$.$ He had read that enrolling late in Part B will result in coverage gaps and penalties.

Questions:

$1.$ Can Michael enroll in Part B$?$ Will he have to pay a late enrollment penalty $($LEP$)$ and face gaps in coverage?

$2.$ What is part B SEP?