Boost the Alcohol in my beer kit? It has finished at a low percentage :(

I have a beer kit brewing, which is finished fermentation (Pretty much), it is a 40 pint lager kit, brewed with 1kg of table sugar, I have spray malt light, and brewing sugar and more table sugar, according to the pint.com.au calculator and my hydro readings, the beer is at just 3.33 percent, can i boost the alcohol content/flavour at this stage? I also have other supplies for wine making, like yeast nutrient etc.. anyone able to come up with a plan for me?

Thanks!

you can try.

Most can kits have 3.3lbs of extract and a couple pounds of sugar.
how much of the extract is fermentable or if there is maltodextrin in the mix the questions start.

5lbs in a 5 gallon batch is going to make a low ABV beer.
I'm sure there is active yeast still and you can add stuff to up the alcohol and add ferment time, but all your going to get is more alcohol.

I'd bottle it and go bigger from the start next time.