I am trying to make my form validate using html and js.

Question

Can anyone guess a valid algorithm to make a form validate using html and js.

Answer 1

you can use javascript for check the input data from the user on submit (e.g. valid or required and more)
look at this:
https://www.w3schools.com/js/js_validation.asp
or
with HTML5 you have new possibilities:
https://www.w3schools.com/html/html_form_attributes.asp

You sould not use only javascript for the validation, because the user can deactivate it in the browser.
On the client side validate the input data with javascript or HTML5.
If you use the data to store it in the database you have to check it furthermore (e.g. java, jsp, php ...).