hi all . i need smart people to help me cause i am failing hard

im trying to use a Vodafone supplied HG659 as a wifi range extender.

i do not want to connect the 2 routers via cable at all ...the sole purpose must be to take my main routers wifi and extend or repeat it

can anyone help talk me through the steps .i looked at different videos etc online but im still failing

something about disabling DHCP that i did.

changing SSID to match the main router i did

i even just pushed the 2 WPS buttons on the 2 routers, they connect but the internet isnt shared.

please help this utter noob