How to safely encrypt a piece of text?

Hello, I want to encrypt a piece of text with symmetric encryption and write it down on paper, so I cannot use verycrypt. The text is human understandable text and not some random number letter mixed key. Due to some reasons I can not use asymmetry encryption because it requires keeping a private key digitally in the same time. I searched the internet and most answers are using openssl and aes256 to encrypt, but I see someone says this method is vulnerable to paddle attack. I do not understand cryptography so I cannot figure out what does this mean, but is there any easy to use and battle tested tool for symmetric encryption like gpg?

Well, GPG has a ‘–symetric’ option. But you could also just encode the private key with base64 and write that down.