How can we track/implement form start and form submissions in SPA and also want to check where user was dropped off?
The easiest way would be to use Direct Calls at each of the form steps and also the form successful submission and form error submission steps. How to implement exactly depends on your website's design / frameworks. Talk to your developers about adding the Direct Calls at every function that renders a form step to the user's browser.
We can track all those things through custom code.
For Example:- custom code for form submission