api forms

i have a form in single page laravel with angular with 5 tables :'( i want to ask about best practice in this case ? 1-should i create function to prepare my date to be mapped to the front end where should data formatting happen ? 2- here file to save this file and log the saved date is too long should i divide it ? 3- i didnot use fill and save i set all the data field by field is it right ? i wished for your advices to make my code good and a long form github example or tutorial which is near to my case . thanks in advance