Can you please share where the Form data will store as lead or any custom model?

If you want to keep the data in any model of odoo addons.

I can give you the example of a custom form from its submit button I have created Lead.

First,  Create a new field with Html type in the crm.lead model.
  

from odoo import models, fields


class CrmLead(models.Model):
    _inherit = 'crm.lead'

html_data = fields.Html('HTML DATA')

Now if you want to show in your view then you can add.

For Website Form, Here is simplest form template.

views/website_form_page_views.xml

​

After that, I applied Action on the form's Submit button, from where the controller will be called ...

controllers/main.py

​from odoo import http
from odoo.http import request

class WebsiteForm(http.Controller):

    @http.route('/form/', type='http', auth='public', website=True)
    def index_page(self, **kw):
        	​return request.render('website_form.form_page_view', {})


    @http.route(['/form/submit'], type='http', auth="public", website=True)
    def contact_form_submit(self, **post):
       	​request.env['crm.lead'].sudo().create({
            	​'contact_name': post.get('full_name'),
	​	​	​'name': post.get('subject'),
		​	​​'email_from': post.get('email'),
		​	​​'mobile': post.get('mobilenum'),
	​	​	​'html_data': post.get('html_field')

       	​	​})
      	​return request.render("website_form.on_success_submit", {})

​

Hi

You can refer to the blog:  https://www.cybrosys.com/blog/how-to-create-website-form-odoo-14

Hope it helps