Archer C6 v2 wifi extender-access point

Hello,
I am new here, i am bad at routing.
I wanted to use my archer c6 v2 as an antenna to my pc (it doesnt have wifi card, i want to connect to main router wirelessly) and i want the router to send 5 Ghz for VR usage. Yesterday i did set is as an antenna, it was pretty trivial, but after i installed Luci-prot-relay, after reset i couldnt get to Luci GUI. I had to debrick it, i dont know, if it was my fault, but it probably was.

Can you help me, please?