I've not used one, but I expect it is somewhat unlikely you can get the hg659 to do what you want.
To solve the problem, it night help you to know the technology you need - you need an "AP client". You can get dedicated AP clients, otherwise any router that runs dd-wrt can be turned into one. As the name implies an AP client acts as an access point (aka WIFI) client, and you can plug the Ethernet cable from your computer into it.
An alternative might be for you to get a WiFi adaptor for your computer. This could be a USB device or if your computer supports it a PCIe card. This might be cheaper.
Of-course, the quality of the connection will be limited to the quality of the WiFi chipset/antenna you get. The performance if these can vary wildly - and you normally get what you pay for. I imagine you want at minimum a device that handles 802.11ac and has at least 2 antennas (so it xsn do mimo)
Another technology to consider would be Ethernet over power line (eg power line adaptors). These are also hit and miss depending on the quality of the gear and your electrical wiring - but have the advantage if not utilising your WiFi spectrum (capacity the WiFi network has). In this context you would get 2 adaptors, plug them into the wall power and Ethernet port and it acts almost like a virtual Ethernet cable. As it can be brilliant or bad depending on your wiring make sure you can return it if it doesn't work.
