Old vsftpd_v1 is missing!

I am doing milestone 1 of module 4, i have vsftpd_v1 to v7 . i am not understanding what to do with them?

please read provided information carefully and perform tasks accordingly. The instructions are very clear to understand.

Where is my old vsftpd.conf file?

You need not worry about the old one. The new one works right out of the box.