@adronia@tiggi.es it is better to do full-disk encryption and make sure your laptop auto-locks after a few minutes of inactivity. If you don’t already have full-disk encryption setup, you will have to reinstall the operating system.
If you only want to keep the directory encrypted and not change it often, I recommend you archive the directory and then encrypt the archive using GPG.
If you want an encrypted directory that you can update regularly, I would instead create a virtual disk with full disk encryptpion.