Migrate arduino project to ESP-IDF (working template)

Ive worked on an arduino project some months. about 6000 lines of codes splitted up in different modules. Working absolutely fine.

Hardware is a ESP32, 4mb, SPI LCD display, Rotary encoder and few buttons, and a TX RX working. OTA update also working fine from arduino, but as i can understand it might need to get into the ESP IDF environment to make sure it will be working correctly (i might be wrong on this).

We want to expand project with secure boot V1 and flash encryption. and we have a hard time making the basic template in ESP-IDF working with our hardware.

So main project is a "Build and flashable code for ESP-IDF latest V." that :
1.is compatible with ESP-IDF
2.Work with our TFT SPI ST7796 LCD screen. just some basic text showing up on screen to verify.
3. Create basic screen where encoder rotation and buttons are noted when pressed to verify working.
4.Migrate our arduino OTA Wi-Fi code to ESP_IDF environment (Or just make new directly in IDF if you prefer). also with OTA_0 and OTA_1 to prevent boot failure by rollback Firmware verion.
5. secure boot V1 and flash encryption activated and working.

We dont know what the best solution is. We need your support on choosing best path for project. Main goal for us is Secure boot V1 and encryption activated and working. All other is working fine now in Arduino code. We might need help later to migrate Arduino, but not needed for now.

We can pay milestones in small steps. but prefer a more long term partner for ESP IDF and C+ coding.