how to give user access rights?

  In Aras you can set 3 types of permission:

1. Who can add item
2. Who can get\update\delete\discover
3.  Who can get\update\delete\discover based on lifecycle state

For example for Part items, goto Administation->ItemType and search (and open) Part itemtype:

1. In "Can Add" tab you can set Identities that allowed to create Parts
2. In "Permission" tab you can see default permission for newly created Part. Permission is an Item that contains list of all Identities and action they allowed to perform (for example update the Part or delete the Part)
3. The "new" Permission can be overwrites by Lifecycle. So if you go to Lifecycle tab and open it, then click on each state and there is a state specific Permission, that now contains list f all Identities and action they allowed to perform (for example update the Part or delete the Part) on this state only.

  You can read more info about the Permissions inside ARAS help (on main toolbar select Help Menu and then Just Ask Innovator)