@Markie1234
You could try this which is prorated to 5 litres from a recipe in a well known book, and uses two of the three hops you mentioned. It will produce an American style IPA of ABV about 6.2%ABV , and 55 IBU which is quite bitter but suits the style. I haven't brewed the beer so can't comment on how it will turn out.
Pale Malt 1.3 kg (mash at 65*C for an hour)
Citra 13,8% 6.3g 60mins
Citra 13.8% 3.3g 10 mins
Simcoe 13% 3.3g 10 mins
Citra 13.8% 9.5g Heat off
Simcoe 13% 9.5g Heat off
Citra 13.8% 11g Dry hop after fermentation ended
Simcoe 13% 11g Dry hop after fermentation ended
If the hops you use have different %AA to those above prorate up or down accordingly
If you want to use some crystal malt for colour and a little sweetness, substitute it gram for gram with the Pale Malt up to 75g.
If you want to only use 1 kg malt rather than 1.3kg be aware that if you do that with the bittering hop quantities above, the beer will turn out more bitter due to the increased hop utilisation in the boil. And 1 kg malt will produce a beer of about 4.8% ABV.
Next if you are mashing in a small SS stockpot I suggest you put it in an oven on a low heat setting to maintain the mash temperature over the mash period. This is what I do.
I also suggest you buy some 'drug dealer' scales which can accurately measure small quantities of hops. Typically available on ebay. Search '0.01G - 500G Digital Weighing Scales'
Finally I recommend you get hold of a book to help you along. Greg Hughes 'Home Brew Beer' is widely available, although there are a few revisions and you might find a s/h copy on ebay. Its full of recipes and the essentials of how to brew.
Hope all this helps.