I'd suggest you start off making builds using PC Partpicker. It doesn't help with understanding to begin with, but as you play around, if you have a genuine interest you'll begin to learn a lot more about PC builds and compatibility.
As for this PSU, yes, the connector will fit.
The GTX 770 uses one 8 pin and one 6 pin connector
The PSU specified use both.
For future reference, to find this information, you'd go to the manufacturers website, or just google the product, and find the product specifications.
Here's a table from Geforce GTX 770 specs:
Thermal and Power Specs:
Maximum GPU Temperature (in C): 98 C
Graphics Card Power (W): 230 W
Minimum Recommended System Power (W): 600 W
Supplementary Power Connectors: One 8-pin and one 6-pin
The table for the PSU:
http://www.seasonicusa.com/images/M12II-Bronze-650-750-850/AM-650-750-850-3.jpg
Under PCI-E (GPU's are PCI cards), you can see that your model provides 4 8 pin/6 pin power connectors.
Hope I helped, and if I'm completely wrong in everything I just said, please correct me.
Kind Regards,
NoobMerchant