I'd like to add some more exterior outlets in my backyard and I noticed a blank panel halfway up a wall. I removed the blank plate and there are a bunch of electrical wires. I've attached a picture of the receptacle. I need to first figure out what circuit these wires go to, but assuming they are usable, what sort of box/cover would I need to put a couple outlets here. I'd like to use an in use weatherproof box if possible. Thanks for the help.

I recently hooked up a computer to my TV with HDMI and when I plugged in the power cord it burned up starting at the end by the surge protector and worked its way up to the PC. The outlet and surge protector as well as TV and PC were fine, just the power cord. We then tried another power cord and it was OK but went to plug the HDMI cord in and it sparked. I'm thinking it was a faulty power cord and the PC spiked and fried the end of the HDMI that I didn't notice but I'm not sure. I used a receptacle tester and it shows both outlets are grounded. No circuit breaker or surge protector tripped. Should I get an electrician to look at the outlets or is this likely a bad power cord issue?