How to authenticate an FTP user?

Question

FTP

Hello, I wrote a small program in Java to connect to ftp.
I have already figured out how and where to connect after switching to passive mode, but I don’t understand why, it does not respond to any commands. Maybe I'm doing something wrong, or something else. There is of course one option that I do not use TLS authentication, since I simply do not know how to do it, if you know, write