TP-LINK Archer C5 Ver 1.2

I really need some help to get started. I'm a bit of a newbie but eager to learn..... can you please point me in the right direction?
Finally i need to set-up my tp-link archer c5 v1.2 as a wireless repeater.

thx Z

Try this: https://openwrt.org/docs/guide-user/network/wifi/relay_configuration