atmega328p, MPU6050, 74HC595, two 7-segment display project

I need an AVR code for atmega328p to be able to read PITCH angle, use LED to display sign (-). Display results on Two 7-Segment displays (-90 to 90) with help of Two shift registers (74hc595). Code needs to make use of LOW Power Mode, The <avr/sleep.h> and <avr/power.h> libraries have useful functions you can call to do this, or you can implement register writes directly by yourself. Add a tare button that, when pressed and held for one to three seconds, re-zeros the display to whatever current angle the board is being held at. If the button is held down for at least three seconds, this tare value should be reset to zero. Write this value to EEPROM so that when the board is powered on, it loads the value from EEPROM to recall this setting. You should provide an LED that illuminates whenever the “tare” functionality is enabled (i.e., when the offset is nonzero). Additionally, add a “freeze” button that, when tapped, locks the current displayed angle until tapped again.