Vesta ssl certificate generation?

Question

Digital certificates

In general, when generating ssl keys in the vest, as it is written in the instructions, an archive with additional keys for the
SSL Certification Authority / Intermediate field should be sent to the mail,
this is the third field, I copied the key first and second, but to fill in the third, you need to copy the keys from two files and insert them here, I thought maybe they are stored somewhere on the server? just where? since they are not sent to the mail ... or are there any other options how to fill in this field? because if it is empty, then the certificate is considered invalid, that's the problem