Hello @Durvesh Jadhav
If the HP laptop was specifically sold with a lifetime/perpetual Office license, it is normally a one-time-purchase version of Office rather than a Microsoft 365 subscription.
For Office preinstalled with a new PC, Microsoft states that the license may use a digital product key, so you may not receive a physical key. Open Word or Excel while connected to the internet and sign in with the Microsoft account you want associated with the Office license. The activation process should detect the included entitlement and associate it with that account.
If you only see options to Try or Buy Microsoft 365, that can mean the installed Office is merely a trial and the PC doesn't currently have a perpetual Office entitlement. In that case, check your HP invoice/order details to confirm that Office Home & Student/Home & Business or another perpetual edition was actually included with the laptop.
If the invoice confirms that Office was included but activation still doesn't appear, I recommend contacting HP support or the retailer first, since they supplied the PC and Office entitlement.
Also, be careful with the term "lifetime Office." Microsoft officially describes products such as Office 2024 as a one-time purchase for one computer, rather than a lifetime Microsoft 365 subscription.
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