Hello,
Thank you for your question.
Yes, with OS Simple Membership - Joomla Membership Extension you will be able do that.
You will need create two groups free and pro, and for that groups select from Joomla admin area who will have access for that groups, for example only registered users.
Remember that only in PRO versio of Joomla Membership Extension you will be able to create PRO group.
ordasoft.com/os-simple-membership-joomla...n#download_component
If you would like any further information, please do not hesitate to contact me.
Sincerely Yours
Taras
OrdaSoft team