What do I need to know if I am going to use FileVault I am going to big travel trip with my Mac and I have think that turn on FileVault will be a good decision, for the case if may MacBooks was stolen.

I have found the stories (https://discussions.apple.com/thread/8301725, https://mybyways.com/blog/macos-filevault-and-sierra-update-get-stuck-when-running-concurrently) that sometimes updating the Mac OS can be broken if I have FileVault turned on due to errors in updating software. In the travel I will not have the ability reinstall my MacBook, so may be it will be better to not install Mac OS updates during the trip.

May be there is something else what I need to know if I am going to turn on FileVault. Some to doand not to do.
Be sure to write down your password and recovery password on a piece of paper and keep in a safe place. 

Be sure to have your data backed up before you leave. Using filevault reduces or eliminates your chance of third party data recovery apps succeeding ( like https://en.wikipedia.org/wiki/PhotoRec ).  Hence, you need to up your backup game.