This clock will be taking time from internet using wifi and it will display it on st7735 display so it will require a WiFi with a working internet connection and no RTC will be needed for this project.
You need to download the Code, Schematics & Gerber file.
After downloading the file just add st7735 library and NTPClient library into your arduino ide.
Then open the TFT_NTP_CLK sketch
And before uploading the code just edit it and you need to provide your wifi ssid and password in it and then,
You need to set offsettime for me it is 19800
Because my timezone is utc+5:30 so
CALCULATE your timezone and edit it and then upload the code.
you can use this sketch TFT_NTP_CLK_7seg.ino to get clock with 7 segment font but for that you need to paste the font file DSEG7_Classic_Bold_20.h in fonts folder of arduino ide to use 7 segment font.