My smartphone can't recognize ESP8266

I tried it but the the serial monitor did not display anything.

Did you follow the directions at HERE

yes I followed but it doesn't work.

Did you get the same output on the Serial monitor?

what Tools>Board have you selected?
I tend to use 'Generic ESP8266 Module'
what particular ESP8266 module are you using?

have you set the serial monitor baudrate to 115200?

No. I didn't get anything

I use 'NodeMCU1.0 (ESP-12Module)'.
No. Serial monitor baudrate dosn't display on my monitor.

Then you are not runing the same sketch. Bye.

have you selected Tools>Serial Monitor to get the Serial monitor display?

yes I selected it and this is displaying:

But 'Server Started' doesn't display.

if you are just getting ......... displayed it is not connecting to the WiFi network
check the network SSID and password?

EDIT: is it a 2.5GHz network - the ESP8266 will not work with 5GHz networks

No I run it

Sorry. I did not understand what you said. How can I test SSID and password?
And اow can I check whether it is 2.5 or 5.

do you connect anything else to the network? e.g. the smartphone?

/* Define WiFi Credentials */
const char* ssid = "hash";/* Your SSID */
const char* password = "12345678";/* Your Password*/

not sure how to check for 2.5/5GHz networks
my network modem monitor displays connections, e.g. ethernet, 2.5GHz and 5GHz IP address etc

No I don't connect anything to the network. And I can't recognize it with smartphone.

where did you get the SSID and password from?

/* Define WiFi Credentials */
const char* ssid = "hash";/* Your SSID */
const char* password = "12345678";/* Your Password*/

From a learning video on YouTube.

to connect to a local WiFi network you need the SSID (network name) and password
do you have a local WiFi network?

No I haven't local WiFi network. Nothing is said about it in the video.