What specific frameworks are you looking for? Object Detection API is a well-developed and appreciated framework among the vision community. It comes with performance benefits, a rich repository of SOTA model implementations many of which are TFLite-compatible.
But here’s a standalone tutorial from keras.io 2 that shows you how to train a RetinaNet from scratch:

  
      

      keras.io
  

  
    

Keras documentation: Object Detection with RetinaNet 8