Good day,

I'm not exactly sure if the following is possible, but I would appreciate any feedback!

I currently have a router/modem (netgear) connected to the internet via a adsl telkom line. I have another mega 105wr router/modem that I want to connect to netgear wirelessly without using cabling.

Is this possible and if it is, what are the steps I need to follow in order to get this working?

Thanking you in advance

Nope.
You need to use a wireless bridge.
The second netgear will not connect to the primary as you envisage.

Thank you so much for the quick response!