How to change internet speed 10mbs 100mbs

i would assume your are talking about lan speed?

you are limited by the speed at which the devices you are using.
what devices are involved,

1. youre network adapter on your pc.
2. the switch, hub, modem or router that you re pc is connected to.

so, you need to replace the device that is limiting speed, you do know most networking devices are 1000mb now.