Wireless - Wired network?

[iBroTuber]

Hi,
I'm new to this forums and a bit new in networks, also english is not my mother language.

Okay, so I have a 2 stories house in the middle of the city, I have a modem/router (All in 1, yes, probably cant change it) provided by my ISP, which is located on the second floor. Problem is, this router doesn't fulfill my needs because it doesn't provide a decent range for my house, so I have very low signal in some parts of it.
I was wondering if I can wire the router with a TP-Link Access Point/Repeater from the second floor to the first floor, because if I use it in wireless mode the original signal would be bad, making the repeater extend a bad signal. So should I set this TP-Link to repeater or AP mode? Can I just wire the router with the TP-Link without problems?
The modem/router is from Cisco, it's a DPC3825.
The AP I actually have is a TL WA730RE , that can be changed for another model.
Thank you

 

[stevech]

Most ISPs must or will agree to change their router to bridge mode. Then you can select and arrange your own WiFi router. That's a recommendation.

Adding an Access Point (AP) is the best way to improve coverage and speed if you cannot place the WiFi router optimally. A repeater (WDS) is not recommended by me for many reasons.

The challenge with the addition of an AP is how to connect it to the WiFi router. Some methods
cat5 cable in attic, under raised floor, etc.
IP over power line - two such devices. Many brands to choose from. Quirky due to noise and attenuation. See the HomePlug/MoCA section on this web site/forum.
IP over existing TV coax "MOCA". Best if coax is in place. I use that.

Don't get "suckered" into these APs or routers saying they are "Amp'd". WiFi is two way, not one way.
Having external antennas on a WiFi router - and replacing them with a few more dB of gain antennas, is nill.