Dario,
Ozgun is correct.
1) Is it possible to change the value of a field of an asset based on the value of another field,( without installing IT PAM) ? (for example relate 'status' values and with location values)
This is no OOTB method to do this. However CA Services may be able to assist with this.
2) Is it possible to make any notification without installing IT PAM?
No, ITPAM is the underlying functionality for notifications.
3) Is it possible to populate fields of an asset with a default value?
As Ozgun stated, information may be inherited from the model. There may also be some customization that can be done to populate default values. But this would also involve CA Services as is not OOTB functionality.