@heartvalley Hi. The order confirmation email is sent when an order is created by the customer.
The responsible function to send order confirmation email is validateOrder() in file qloapps_root_dir/classes/PaymentModule.php. The html and txt email templates for the same are:qloapps_root_dir/mails/en/order_conf.html
qloapps_root_dir/mails/en/order_conf.txt
In file PaymentModule.php, the code after line number 843 (may vary) creates data for the mail template and the mail is sent using Mail::Send().
You can modify PHP code and templates to suit your needs.
Regarding your second query, to show available room numbers, please raise a ticket at https://webkul.uvdesk.com/en/customer/create-ticket/ so that we can have a person to person discussion.