Modern Events Calendar is designed in a way that you can sendemails from its panel. For instance, the default feature hasauto-confirmation and auto-verificationemail options. These emails are sent once a booking in done on your website.
There might be two reasons behind it, if you are unable to try sending emails from Modern Events Calendar.
Note: you might need a third party plugin for extensive emailing option on your WordPress website
Here we can see a conversation from the Modern Events Calendar‘s support desk explaining how to enable to disable this feature.
I try to send an email from MEC but my trying is failed. Now I have a question, how can I send confirmation email or new booking email?
Sending email from your website is related to the host, you need to contact to host provider form enabling the mail functions in your host.
It's what do you need to do in MEC: make sure to turned on auto-confirmation and auto-verification on MEC Settings > Booking
If the above description is done and still doesn't send an email in your inbox or spam folder you need to use the third-party plugin for manage emails. e.g: SMTP Plugin