You can download my program for a nice APRS tracker for the Lilygo T-Echo 433 MHz. This is a PlatformIO project in Visual Studio Code. In the macro (#define APRS_CALL "CALLSIGN-SSID"), you need to enter your callsign and SSID. Double click reset button, to enter in bootloader mode, for firmware update.
Pressing the user button turns the module on when it is off. Pressing both the user button and the touch button simultaneously turns the module off. A short press on the touch button lights up the screen. A long press on the touch button triggers the transmission of an APRS frame. Pressing the user button enables or disables the tracker (APRS frame transmission).