For all the Business Account I need to have Read Only access and for the person account I should have read Only, Create and Edit permission. Where I can make the changes or settings?
Under Sharing Settings, set the Organization-Wide Default for Account to Read-Only. Then create a Criteria-Based Sharing Rule to share all Person Accounts (via Record Type) to all internal users in Read/Write mode. Then, if needed, create another Criteria-based Sharing Rule to share all Business Accounts to only the select group of users allowed to edit them. Finally ensure the users all have Read/Create/Edit for Account in their profiles or a permission set.