It does, but it’s super dangerous to do unless you have it wired up properly. Proper installations will use a special connector so you can’t plug anything else into that receptical, and will have it interlocked against the main breaker - you can’t plug anything in without disconnecting from the grid. The dangers of doing it amateur-hour are:

• You now have a cable that you can unplug and have live ends exposed - which if you don’t realize is connected to an active generator is super dangerous, and even if you do one slip and you are now the ground conductor
• If you connect the generator while still connected to the grid, your generator is almost certainly going to be out of phase. This will probably cause damage to your generator and anything else plugged in at the time
• If you don’t have an interlock and run the generator while connected to the grid (say during a power outage) you will be back-feeding power into the grid. This is super dangerous for anyone coming to fix the outage, as things that they’ve isolated to fix can still end up being live