Two suggestions and 1 Caution -
1) Consider Index Funds or Exchange Traded Funds (ETF's) rather then individual stocks. You do need to do your homework though on these - look for low cost reputable ETF's that invest in actuals rather then paper.
But more broadly you should come up with a broad plan covering the how, what, when etc.
It sounds a bit daunting initially but also reveals the type of things you should know before committing your hard earnt to the markets. Stuff like how will you measure success or failure. at what point will you say I got this one wrong and sell?
You might want to have a look at some article on the following site. I have no association with them just have been on their email list for some years -
http://www.alphaim.net/
This is a recent article -
http://www.alphaim.net/power_newsletter.html
2) Have a good look around here - Plenty of free article etc
https://stockcharts.com/articles/
Take your time, think about it ?
The caution ? - Consider where we are in the current economic cycle, plenty of Economic Clocks and articles around.
Attached is one from Brit, James Montier from GMO a Boston-based fund manager with $US99 billion in funds under management, co-founded by highly regarded veteran Jeremy Grantham (another Brit with US citzenship I think).
The article is titled - Late Cycle Lament: The Dual Economy, Minsky Moments, and Other Concerns
Finally I'm just pointing you to general ideas etc nothing more - its up to you
BTW a google Finance link to that Energy referred to by the OP -
https://www.google.com/search?tbm=fin&ei=OJlgXJG4KcHnvASkvb2oDw&stick=H4sIAAAAAAAAAONgecRozi3w8sc9YSm9SWtOXmPU4OIKzsgvd80rySypFJLiYoOyBKT4uHj00_UNK3OMMyxLijJ4AAkYMKg8AAAA&q=LON%3A+UKOG&oq=LON%3A+UKOG&gs_l=finance-immersive.1.0.81i8k1.16280.16280.0.17964.1.1.0.0.0.0.167.167.0j1.1.0....0...1c.2.64.finance-immersive..0.1.166....0.maYMNSSL9-M#scso=_S5lgXMm1JIr_vgT_7IAI2:0
Good luck - please do your homework and preparation carefully.
GMO the-late-cycle-lament-minsky-moments-&-other.pdf