I want to be able to read & answer my work mails from home with my home Office suite, without mixing up all my private & pro stuff. How to solve this?
I am going to assume you are actually using a perpetual Office installation instead of Office 365 since that is a subscription and requires a Microsoft Account. The simplest method to solve the problem you describe, is to first link to a Microsoft Account that does not have access to Office 365 subscription, before you add your work email to Outlook.
I'm using a Microsoft Office Suite with Word, Excel, PowerPoint, and Outlook. Each of these tools are not connected to any account.
As soon as I add an Office 365 mail account in my Outlook, it instantly connects this account to the whole Microsoft Office Suite (Word, Excel, PowerPoint).
Office 2016 and newer are designed to be linked to a Microsoft Account. Many of the features that have been added most recently are designed around cloud storage. I have personally experienced the situation where I have a perpetual Office 2019 installation, when I log-into to my Microsoft Account with an active Office 365 subscription, it will start to receive Office 365 only updates.
However, linking to a Microsoft Account is not actually required to use any version of Office, your situation only exists due to the fact your work account is linked to a
E1 Office 365 subscription.