qmk_firmware_custom/layouts/default/numpad_5x6/default_numpad_5x6/keymap.c

#include QMK_KEYBOARD_H

const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
	[0] = LAYOUT_numpad_5x6(
		KC_ESC,  KC_LPRN, KC_RPRN, KC_PSLS, KC_PAST, KC_PMNS,
		KC_A,    KC_B,    KC_P7,   KC_P8,   KC_P9,
		KC_C,    KC_D,    KC_P4,   KC_P5,   KC_P6,   KC_PPLS,
		KC_E,    KC_F,    KC_P1,   KC_P2,   KC_P3,
		KC_LCTL, TG(1),      KC_P0,       KC_PDOT, KC_PENT
    ),
	[1] = LAYOUT_numpad_5x6(
		RESET,   KC_LPRN, KC_RPRN, KC_PSLS, KC_PAST, KC_PMNS,
		KC_A,    KC_B,    KC_HOME, KC_UP,   KC_PGUP,
		KC_C,    KC_D,    KC_LEFT, KC_NO,   KC_RGHT, KC_PPLS,
		KC_E,    KC_F,    KC_END,  KC_DOWN, KC_PGDN,
		KC_LCTL, _______,      KC_INS,      KC_DEL,  KC_PENT
    ),
};