I use McAfee security software and if I attempt to access the web address you supplied, it is blocked as per the following screen shot. Therefore, I suggest that you stay clear of it. They are a scam to get your banking details so they can then access your money.

Screen shot of the message.

Dear cellyoolar_006,

Thanks for posting in Microsoft Community.

First, my pleasure to assist you.

As per your description, please don’t worry, we can work together to narrow down and resolve the situation.

Generally, if you have purchased Office 2021 with product key, before you begin install and activate Office, you will need to Redeem your product key to associate it with your Microsoft account.  Go to office.com/setup and sign in with your new Microsoft account* and then enter your product key to redeem it. Redeeming your key is what add your Microsoft account to Office, and you only have to do this once. 

If you redeem your Office key to Microsoft account, you may access that account https://office.com/myaccount with your associated Microsoft account to check whether the Office Home and Student 2021license is listed under your subscriptions and click to reinstall or activate with your Microsoft account. For your reference: Download and install or reinstall Microsoft 365 or Office 2021 on a PC or Mac

Your understanding and patience will be highly appreciated. I hope that you are keeping safe and well!

Sincerely,

Waqas Muhammad

How it is not legit if you activate online via Microsoft online activation and it is confirming that your office is activated ?

I mean if the key would be not legal Microsoft online activation should not allow it to activate ? Or not ?

How can anybody prove that i bought this key online if it is activated via Microsoft online activation and it says office activated in status.

Or i need some kind of box or papers to prove that my office is kegal or something ?

How does it work ?

For example: if i would buy office via Microsoft store with a box and the key inside wrote that code in .txt and discarded that box. Does it mean i'am legal not legal user ? Who can prove that i didn't bought that code online ?

I don't understant Microsoft logic if it is allowing users activate office online via Microsift online activation with a codes bought on third party websites and then say that thoses codes are not legit...****...

This is NOT helpful! I have a valid Microsoft product key for Office 2021 but the ONLY link provided takes me to the Office365 website and that is NOT what I purchased. There is no way to actually download Office 2021. Why is this?