@Ahmadkhan Can you try plugging your laptop with a cable to the router, to see if the speed will be the same? And if the speed is the same ,you can try plugging it into your laptop, to rule out the router as an issue.

Not sure what exactly you mean with "sharing traffic", perhaps you mean, you get extra bandwidth/data cap when using specific services?

when I tried with the cable, is still giving me the same speed of 10mbps.

@Ahmadkhan Did you try with the laptop plugged in directly with the cable, without using the router (the cable which goes into the WAN port of the router, to go into your laptop)? If yes, and you still get 10mbps, then its an issue with the ISP.

@ku4eto That's working amazingly I got 80Mbps when I download from Google drive(google server)

@Ahmadkhan 
Okay, then that means the issue is indeed coming from the router.

Can you check if you have not enabled the QoS (Quality of Service) option? Or the bandwidth limitation?

@Ahmadkhan 

Okay, lets try backing up your configuration (System -> Backup & Restore), and then do a factory reset from the same menu.

Once the router resets to factory settings, try using checking the download speed again, while connected to the router.

As for warranty: you should check with the place from where you bought the router.

@Ahmadkhan Go to Network -> Internet, and try setting the Network Negotiation to 100Mbps. It could be the connection is auto negotiation link speed of 10 Mbps.