Odoo is the world's easiest all-in-one management software. It includes hundreds of business apps:
CRM | e-Commerce | Accounting | Inventory | PoS | Project management | MRP | etc.
If you want to inherit the access of the other group you can add those group in implied_group field like(it is m2m field):
Meaning of implied_ids field: Users of this group automatically inherit those groups
<field name="implied_ids" eval="[(4, ref('base.group_user'))]"/>
<field name="implied_ids" eval="[(4, ref('base.group_sale_salesman'))]"/>