So I downloaded Picocrypt on my Mac and encrypted a folder but turns out I also need to decrypt it every time I need to access it and again go through the encryption process after I make changes to the folder.
Is there a way to encrypt folders and being able to use them without going through a time consuming decryption process?
You could use e.g. https://cryptomator.org/ which mounts the vault as a drive for a certain amount of time.
Keep in mind that while your encrypted folder is opened anyone who gets physical access to your PC can access the data.
Have you tried something like VeraCrypt or Cryptomator?
You do need to decrypt but it is as simple as enter a password. It stays unlocked until you lock it again.
Create an encrypted APFS disk using native Disk Utility. Probably you can even store the password on the Keychain and unlock it with your fingerprint (I guess, never done it myself).
Inside it, picocrypt only the really sensitive stuff you don’t need to decrypt everyday.
I’m not sure about Intel Macs, but please don’t use VeraCrypt on an Apple Silicon Mac. It requires system exrensions, which will only run in a less-secure mode of MacOS. Test it inside a Linux VM in UTM or Parallels if you want.