Configure 1 router with "normal" internet and 2nd router with VPN

Hi everyone,
sorry for not answering and thanks for your help. I was busy with work so I couldn't work on my project. I couldn't quiet follow your instructions because I'm too inexperienced to understand some of them. But I played around a bit and posted my experiences here if you are interested. I flashed OpenWrt on some cheap TP-Link Archer C6 v2. These are my experiences