3) An SQL console is opened for a specific system. So if you use the CREATE SCHEMA statement the schema is created to which the SQL console is connected (pre-condition: of course you must have the privileges to create as schema).
4) Please read the documentation. All is described there. It makes no sense to duplicate it here again.
Further question: I do not know if your HANA db is used for an ECC system as db or if any ECC tables are replicated into that system. In case your HANA system is used as primary DB per naming convention you should have a "SAP<SYSID>" schema (SYSID is the ID of your ECC system) which acts as your "ABAP" schema containing the ECC tables. But the name could also be different, depending on that whatever your admins have chosen. Please check that with your admins or system reponsibles.