How to pause throttling and blocking of out-of-date on-premises Exchange Servers

AbdullahGamal >>so if the 90 days balance is added on 1st Jan every year. . .If i started using them on 1/3/2023, the new balance will be added on 1/3/2024?

It's by calendar year Jan 1 to Dec 31, not 365 days from the time you start using them. At the start of each calendar year you're granted 90 days, and you must use them within that calendar year (e.g. for 2024 pause days use them sometime between Jan 1 2024 and Dec 31 2024) or lose them; they won't carry over into the next calendar year.

Tip: Enforcement pauses take effect immediately. To get the most out of your pause days don't pause enforcement until a day or two before throttling is scheduled to start (you can see the throttling scheduled start date in the report).