Let clients plan online meeting

Let clients plan online meeting

Hi all,

I'm wondering what the best solution is to have a planning system where clients can book an appointment (online) and where that booked appointment is visible in crm. Also need notifications when clients don't book within a certain time periode. 

Clients don't have access to Zoho. There is a website that can be used and clients have access to a Creator app. 

Thanks in advance.