The bikes on the Home and Rental pages are added with the Vamtam Beaver Builder so you have to edit them manually:

Guide to Vamtam Beaver Builder

Same for the bike single-view page:

We recommend you to save all column/row layout before editing following this instruction: !

As soon as you hit Book button, you'll access the Booked-WooCommerce products:

Add "Booked Appointments Service" products for each rent-service:

Please note that this option is available if Booked Add-On: WooCommerce Payments is enabled/

Full plugin's documentation:

Payments with WooCommerce — Use Booked with WooCommerce to allow your visitors to purchase their appointments and checkout using WooCommerce.

Please check on the setup instruction here:

Vamtam Beaver Themes: Guide to WooCommerce

Go to Appointments > Settings > Custom Fields > Select the calendar > Add the "Product selector" field and the products you've added in the previous step:

You can also customize the booked custom fields and time slots:

Beaver Builder Theme: Guide to Booked Plugin