scc8 target system

Dear Expert:

on SCC8, I 'd like to copy only customizing so I choose profile-SAP_CUST.

1.what is target system ? is this source system for my export client?

now i have only one SAP system ie. MNP

2.copy mode = delete and recreate

is the system will delete data from my MNP (source)? too?

please advise.