Yes, this is possible. It depends on the member start date, when the member enters their billing details, and how members sign up.
If your members are signing themselves up via your Cobot Homepage, or via a link that you sent them, Cobot will generate an invoice/charge them for their membership fees on the date they have chosen as their membership start date.
For example: if a new member signs up today and today is their start date, then Cobot will create an invoice for their membership fees immediately. If the new member signs up today, but their membership does not start until a date in the future, then the invoice will only be created on that date.
To automate this process, you will first need to connect Cobot to a payment gateway. If your Cobot account is not connected to a payment gateway and there is no payment method on file for that member, then you will need to process payment on that invoice manually.
After you have set this up, you can make it mandatory for your members to enter in a payment method before they can access their member portal. To do this, go to Customize » Features » Paymnets and activate one of the options there.
If you add the member manually, Cobot will still generate their first invoice on their membership start date as outlined above.
You can then add their payment method to their member profile and process payment on the invoice. To do this, go to Invoicing » Past Invoices » Charge.