Possible solutions of your questions

Hello. Bitrix  does not support creating backups on ftp without a special plugin.

What plugin?

in the admin site to configure backups either locally, they will be placed on Your VPS and it should be spent, dopolnitelnoe place, or You can save backups in the cloud Bitrix, some disk space there is free. If You want the backup was done remotely on the server, for this you need a plugin, but it is paid.