Yes you can freeze bananas to make them last longer.
To freeze bananas you should cut the bananas up or at least remove the bananas from the banana skin or banana peel.
Then place the bananas in a Ziploc bag or freezer bag and then remove the air from the bag and freeze them as normal.
The frozen bananas will last for up to a year in the freezer but the longer the bananas are in the freezer the less fresh they become.
So it's best to eat the bananas within 6 months of freezing them.
You can freeze bananas with the skin on but they will turn mushy and brown in color.
So it's best to remove the banana peel first and then freeze the bananas.