I posted this question on the phpmanager forums and didn't get an answer. Can any one here answer this?

Does phpmanager do automatic recuring payments? or does it automatically remind the customer that they need to pay?

no. You have to set up those recuring payments from your 2checkout, paypal, then paste the link to your phpmanager.

no and yes
VNPixel answered the first (no)

the second: yes it will generate invoices for upcoming payments. You can either manually send them out by clicking on the invoice (should show on the admin homepage for phpmanager)
there is also a script you run through cron to auto-send invoices.

So phpmanager won't store credit cards and autobill them via Authorize.net?

Nope