Hello, @Aroni Chakraborty !
The Azure free account gives you $200 of Azure credit to use for the first 30 days as you explore Azure services, but what happens when you've used all of your credits? There are a couple options:
Convert to a Pay-as-you-go account
I know that you said you didn't want to spend any money but it's worth noting that the natural progression of the Azure free account is eventually to convert to a Pay-as-you-go account if you want to continue using Azure services:
What happens once I use my $200 free credit or I'm at the end of 30 days?
We’ll notify you so you can decide if you want to move to pay-as-you-go pricing, enabling you to purchase Azure services beyond free amounts. If you do, you’ll keep getting access to all the free services. If you don’t, your account and services will be disabled. To resume usage, you'll need to move to pay as you go.
Continue to use popular services free for 12 months or 40+ always free services
While there is a set limit on free credits (so no more free credits once they've been used), you can continue to take advantage of a long list of services that are free for 12 months in addition to 40+ always free services. Check out the Azure free account page for the most up to date information.