There are many solutions on the market for managing events or services on a website. Amelia Booking is a plugin that installs on the WordPress CMS and offers a turnkey booking module for beginners while also offering expansion options for developers.
This plugin is suitable for service activities such as healthcare, personal care, events, coaching, and training. Highly rated in the WordPress plugin directory, it has over 80,000 active installations. It is developed by a Serbian company (TMS) that updates it regularly. The free version is quite limited, but there are several paid plans that offer more features for an annual subscription or a lump sum payment, allowing you to tailor your budget to the type of project.
Amelia Booking allows you to create events or services that can be booked using a dynamic and customizable form. The number of places can be limited, and when the number of reservations equals the number of available places, the time slot becomes unavailable or not, depending on the settings established by the user. It is necessary to create and assign different employees to the services, which allows you to customize schedules based on their availability. It is worth noting a large number of options, such as the ability to set waiting times for each consultation. Paid versions of the plugin offer additional options, such as managing locations and resources available to employees (for example, a hair salon chair). Reservations can be paid for with payment gateways like Stripe or PayPal, paid on site, or offered for free.

The integration of services and booking forms on the website is done with shortcodes, which allows you to create custom pages with a pagebuilder or simply use the plugin's default display, which supports the creation of individual categories. The visitor can view upcoming events in the form of a calendar, which is also integrated with a different shortcode into the website pages.
Customize the application according to your needs
Although there is no template system for formatting the booking form fields, it is possible to modify its appearance using a variety of style settings. The basic form can be expanded using a custom fields system that supports the most common fields. It is possible to add text boxes, radio buttons, a select box, a date picker, or an attachment picker, for example.
Translation strings can be edited with Poedit, allowing for customization of hard-coded texts, and the plugin is compatible with WPML if the webmaster wants to create a multilingual site.
An interesting aspect for developers is being able to access the application code with hooks that allow them to graft their own PHP functions to the different stages of the booking process, for example to display certain information dynamically. Hooks are also available in Javascript to interact with the extension in the front-end part of the code. In addition, an API endpoint library is available to allow Amelia Booking to interact with other systems, for example a mobile application.
There's also a template system for adding custom text or fields to the body of emails. The plugin integrates SMTP email delivery without the need for an external extension. Notifications can also be sent via SMS or WhatsApp.
Amelia can work with or without WordPress user management, providing front-end access to user bookings, allowing users to access, modify, or delete their personal data. The large number of configuration settings and features is a strong point of this plugin and demonstrates its ability to adapt to different needs.
Sources:
WPBeginner
CSS Weekly