You must crush and mash the malt, which is essentially making oatmeal at a precise temp range and holding it there until the starches in the malt are converted to sugar. At that point you have un-hopped wort, and you'd proceed from that point as you always have with extracts - boil, add hops, chill, pitch yeast. The middle of the road target temp you should use for the mash is 152 degrees Fahrenheit. At that temp both the alpha and beta enzymes will do their job well and convert both the simple and complex carbs to sugar. Too hot and you end up with un-fermentable dextrins, and too low you'll end up with a super dry and thin beer in the end as all sugars will ferment out leaving no body or malt sweetness.

Scaling down from a brewery volume is complicated when done with pen and paper, but thankfully there are many resources and calculators to help. It's also complicated by the need to know your specific system efficiency, which has a direct impact on the amount of grain you'd mash in order to attain your target gravity. 12.5 degrees Plato is equivalent to 1.050 Specific Gravity, which is usually the scale home brewers use to measure gravity. Knowing your typical mashing efficiency on your system and the target SG will dictate how much grain you will need to mash. On average, I typically get 5pts/lb, so I would mash 10lbs of grain to get an Original Gravity of 1.050.

The hops is another sticky wicket :-) You really need to know the target IBU's in order to calculate what you should use. The timing is valuable information, as it shows two hop editions, one for bittering and one for aroma respectively at 60min and EOB. An ESB by definition (if that is the style they are making) should be 30-50. Check out http://www.bjcp.org/2008styles/style08.php#1c

If you can get a target IBU for bittering and a target for the aroma, then you can find many online IBU calulators that will tell you how much to add at the prescribed times.

I hope this is helpful.