How you build your form and design your site is really up to you - Machform doesn't have the type of templates you're after built in.
Machform is designed to work with systems like Wordpress, WIX, Joomla, Drupal and all those sorts of web builder systems. (that's the site design side of it).
Machform itself is about building the forms, not the entire website.
You can build an event registration form with Machform no problem, but it may not have all the functionality of typical event systems because that's not its primary purpose.
It also has payment functionality built in, utilising Paypal, Stripe, Authorise.net and so on. You need to set up the form and then set up the payment facility you want (including setting up an account with the chosen payment gateway service).
How you build your site design is up to you (whether you use WIX or Joomla or Wordpress or any similar thing), Machform will integrate into any design - but it doesn't have those sort of site templates built in. it does have some basic colour and font type themes, but nothing along the line of what I think you're asking for.