In reality most commercial aircrafts can autoland (with the exception of some smaller RJ and turboprops)
To do this the aircaft must have a "fail-safe" AP logic, meaning there has to be 2 or more autopilots installed.

What FS default Boeings simulates is somewhat of a "single channel" autoland, meaning the aircraft will nicely follow the glideslope and track the localizer. But it will not actually flare and land it for you. You have to disconnect the AP prior to DA/DH and do that by yourself.

But there are several payware addons that actually simulates multiple AP's