You can bridge your wifi and your ethernet adapter and that will allow you to give network connection to your other router.
There are tons of posts on these forums of people who tried this method and had very lousy results, windows and the networking hardware is just not made to to do this efficiently.
Here is the three best ways to accomplish your task in order of the best option:
1) ethernet cable from primary router to secondary router
2) Powerline network adapter (a 500mbps or better kind)
3) wireless bridge to receive wifi and then output to ethernet to secondary router.
Also if you want the secondary router to be able to share file and printers you will want to make it an access point instead of a normal router. An access point is classically an extension of an already established network, it allows the primary router to handle all of the routing/addressing and it just allows you to have more wireless/wired clients.
Some routers have easy mode settings but all routers can be changed inot access point mode. You will need to disable dhcp server, disable nat and spi firewall, change the secondary router to an IP in the same subnet of the primary router (subnet is the first three octets of the ip address, most routers default is 192.168.1), set the gateway (could also be called lan) ip address and dns to that of the primary router, and you will plug the ethernet cable into a LAN port of the access point and not the WAN port.