SAP BW4HANA and ECC 6.0 on Oracle DB

Good Day Experts,

I have some questions regarding the BW4HANA connection to ECC 6.0.
Can I connect my BW4HANA to ECC 6.0 box with oracle DB?

Can I installed the corresponding business content of BW4HANA on ECC? Which version of the business content to use?

Can I get the full use of the business content installed on ECC? Like activating extractors, Flows, transformations, cubes, ADSOs, Composite Provider, ADPM, etc?

Which approach is more appropriated? Greenfield? Brownfield????

Any recommendation?

Many Thanks

Pat