SAP RISE connect with SAP ECC on-prem

We person RISE with SAP connected AWS, and Customer ain subscription connected AWS.

site to tract VPN is utilized to link these 2 subscriptions.

I privation to link SAP ECC strategy connected lawsuit ain subscription with SAP GTS strategy connected RISE .

Can we usage RFC, IDOC straight ? oregon a unreality connector is needed? what different options available? pls explain