issues seen within script. What am I doing incorrect here. #14

What am I doing wrong here? Following the directions given within the script in comments & I receive this error.

⚠️ Error in line 31: The term 'New-CryptographyKey' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and
try again.

Furthermore, I am also getting this error as well.

Enter path to file: D:\Test
Enter password: 123

⚠️ Error in line 121: Cannot convert argument "inArray", with value: "123", for "ToBase64String" to type "System.Byte[]": "Cannot convert value "123" to type "System.Byte[]". Error: "Cannot convert value "123" to type "System.Byte"
. Error: "Value was either too large or too small for an unsigned byte."""