I'm delighted to hear your interest to upgrade your QuickBooks subscription, @vinodkharbash-gm.
Let me walk you through in doing so.
- Click the Gear icon.
- Select Account and Settings.
- Go to the Billing & Subscription tab.
- In the QuickBooks Online section, click Upgrade.
- Choose QBO Plus, select Upgrade.

- Confirm your payment information and click Save.
Just in case you need it, you may check out this article that tackles how to upgrade your QBO subscription: How do I upgrade my QuickBooks Online subscription?
Fill me in if you need a hand with managing your account or in navigating around QuickBooks. I'm glad to help.