Hello Kazi Golam Arefin
Welcome to Microsoft Q&A Platform, thanks for posting your query here.
If your Azure subscription is a trial subscription and it is ending soon, you may not be able to extend it directly. However, you can upgrade to a Pay-As-You-Go subscription: If you upgrade your trial subscription to a Pay-As-You-Go subscription, you can continue to use Azure services beyond the trial period. You will be charged for the services you use, but you will not have to worry about your subscription ending. To upgrade your subscription, go to the Azure portal and select "Subscriptions" from the left-hand menu. Then, select your trial subscription and click on the "Upgrade" button.
Hope this helps.