Is there a way when sending an email from Salesforce to have one Company e-mail address (standard and forever) instead of current user's personal email ?
You can use org-wide email addresses in this case.
If your Salesforce org requires users to share a common email alias, you can define a list of organization-wide addresses for each user profile. When sending email from Salesforce, users with these profiles can select their own email address or the organization-wide email address for the email’s From field. Replies are delivered to the selected address.
- From Setup, enter Organization-Wide Addresses in the Quick Find box, then select Organization-Wide Addresses.
- To manage organization-wide addresses, use the available options.