My Home network is too slow(10 min to transfer 100mb)

Wow, I'm surprised that works. Both of those are afaik just supposed to allow someone to connect the best way they can to a computer or master device. I would have guessed that even if hooking both up to the internet in this way worked, that they couldn't see each other.

You should probably get a cheap wired only router, and hook them to it and together that way, and only use the ethernet port of the modem. It should act as expected set up that way. TBH I've never even used the USB connection on any modem.

What he said. Pick up a wired router (assuming you don't need wireless connectivity).

Unplug the power to the ADSL modem, unhook the USB cable, hook the LAN port on the modem into the WAN port on the router. Pick up a couple of CAT5e or CAT6 patch cables and hook them to the LAN ports on the router, and hook the other ends of the patch cables into your PCs. Plug the power cord into the ADSL modem and the router.

That's it for the physical connections. Try the connection and see if it works after 2-3 minutes of waiting. If it doesn't, then you probably have to set the router up to authenticate with your ISP. If you get stuck, you should be able to use the documentation that comes with the router to access the router configuration, and then your ISP's Tech Support should be able to help you get your new router set up to access the internet via your ISP.