Gateway Registration Using EUI-<id>

Hello All,
I am new to LoRa & LoRaWAN technology and evaluating it. While evaluating I am trying to connect the gateways which are registered on the TheThingsNetwork(TTN) gateway Map using the eui- of the other gateway shown on the TTN map.
Here I have connected the three to four gateways of other from different location from my near by places in my TTN Account.
Now, here my question is that I am registering the gateway to test my end device(node), which are available near by me with there eui- from the TTN maps. After registering the gateways, may I connect my device to the gateways(which are registered in my account) and send/transfer my data to the application server…??

If I am going wrong then please correct me and guide me for the proper settings ….

Thanks
Sachin