N300 Wireless Router error connecting devices

[Harrisonuzurv]

Cable Internet from Motorola modem is flowing correctly. Please see attached photos to rule out modem issues. Purchased this netgear N300 wireless router used from a friend. Its network name is netgear74. I have tried entering the key/password on many devices and still no connection to any device. Trying to connect to a new wireless network on both my Macbook air and Samsung S10 android just leads to timeout errors in a browser.

[plemans]

Any used devices should be factory reset and setup from factory. 

Have you tried this? 
Push and hold reset for 7-15 seconds while its powered on. Then simply follow the install guide found here: 

https://www.netgear.com/support/product/WNR3500Lv2.aspx

[antinode]

> [...] Its network name is netgear74. [...]

   Not "NETGEAR74"?  Case matters.

> [...] I have tried entering the key/password on many devices and still
> no connection to any device. [...]

   Which "key"?  Which "password"?  Have you tried WPS?  Or a
wire-connected device?

> [...] Trying to connect to a new wireless network on both my Macbook
> air and Samsung S10 android just leads to timeout errors in a browser.

   Huh?  You lost me.

   Visit http://netgear.com/support , put in your model number, and look
for Documentation.  Get the User Manual (at least).  Read.  Look for
"Types of Logins", "Basic Wireless Settings", and "Troubleshoot".
Further reading might not hurt, either.

> Push and hold reset [...]

   Usually a good start for a used device.

[Harrisonuzurv]

Plemans - I really appreciate your time trying to help me troubleshoot. I did as you suggested and took a bobby pin to hold down the "Restore Settings" button in red for 10-15 seconds on the back of the router. This was before I connected it to the modem.

So then once I connected to the modem, I can see NETGEAR74 appear on my macbook air network options.   I connect to it on top right of my screen (in the airport) then a netgear window pops up.  After 90 seconds of testing the connection, it asks me "Do you want the Genie to help connect you?"   If I click No, nothing happens, as if the button doesn't work.  When I click yes - it goes through the images below ... and after 2 minutes of "checking" and "pending" it gives up, and disconnects me from NETGEAR74.  Tries to find a new network at that point.  Yet all of the lights on both the modem and the router look correct, as if all information is flowing smoothly.   Please see screenshots & the original photo of the router + modem.

[Harrisonuzurv]

Hmmm ... looks like the screenshots weren't coming through when I checke the post.  Trying a different way.

[Harrisonuzurv]

Photo of Netgear Genie asking Yes or No

[Harrisonuzurv]

Genie checking for internet connection ... 60 seconds here ...

[Harrisonuzurv]

Last one ... NetGear Genie trying to apply internet connection settings before it "times out" and gives up - disconneting me from NETGEAR74 and trying to find another wifi network instead.