Routers are like cars.
All cars have the same basic functions of getting you from point A to point B.
Some cars are small and slow and can only hold one or two people.
Some cars are large and fast and can hold 6-8 people.
Routers are similar to cars. Your internet depends on your router.
Some routers transmit data slow, some transmit it fast.
Some routers can support 1 connected device, some routers can support up to 15 connected devices.
Your internet experience is extremely dependent on the quality of your router.