Hello Vaibhav,
it is not really clear to me why to are using a submit form to call a function with UI5 coding. I assume that your application is a UI5 application in general, so you can use a UI5 button and add a controller method to the press event which does the job.
Also using the attachinit method of the UI5 core is not right here, because that event will not be triggered anymore, cause your UI5 core is already loaded at that moment.
Can you share more of your coding to getter a better insight (e.g. UI5 bootstrapping, general set up of your app, ...).
Best Regards,
Florian