Look into how to setup a wireless bridge. But it all depends if the routers firmware (both) support it.

 

I'll look into that

 

You have to be able to edit/modify the firmware. I looked into a few years back.

 

Yes, the router will have to scan signals around and connect to them. I'm not really sure how it's done with their software config.

Sorry I can't give you more specific advice, but its probably been 15 years or so since I've done that. I was using custom router firmware from DD-WRT as well. Here is DD-WRT's page on how to do it with their software.

I never had much success with DD-WRT, but Open WRT is great.

 

Just put it into bridge mode? I don't think you have to mess with firmware or anything. Just go into advance settings and toggle bridge mode on/follow the pop ups in wireless settings.

 

Yes, but also depends on how old your old router is. It may not support some of the newer standards and security features. If speed and security are not your concerns, or your router is not too old, then sure.

I tried that with an old router few months back, and I would've had to downgrade my main wifi to make it work. Decided it wasn't worth it, and picked up a range extender compatible with my new router. Much happier with the outcome, and almost hassle free. I believe the ethernet port on the range extender can be used to plug a PC in, but double check for your particular setup.

 

Yes, you can repurpose your old R6300 router as a wireless bridge or adapter. Connect it to your PC via Ethernet and configure it in bridge mode. Ensure it connects to the main router downstairs wirelessly. Check your router's manual for specific instructions.