Oh, I have Win 11 Pro. Are you saying BitLocker comes with it?
That's correct. I don't have Pro, but from what I have read, BitLocker is designed to lock disks, not individual folders, so you will have to create a virtual disk in order to be able to lock an individual folder with BitLocker. Details Here:
Yes, it's an annoyingly long set of steps for something that should be as simple as right-click, lock, enter a password. But, assuming you just have one folder to lock, it might be acceptable.
Also, think about what you're locking. If it's folder that has gigabytes of videos, that will take a long time to encrypt. I would look at one of the folder lock programs that do not do any encryption in that case. But if it's a folder of sensitive Office documents, then encryption is ideal.