I think that you will need the right level of sugar. It is what the yeast turns into alcohol, and too little will cause fermentation to cease prematurely, yielding a too low alcohol content. (Unless, of course you are wanting to make a low alcohol version)
Too much sugar, ie sugar still present after fermentation ceases will of course sweeten the flavour of the drink. Although some beers are sweet, lager tends not to be, so hopefully, a good recipe will not have excess sugar remaining after fermentation.
When I brewed, back in 1960's, a book by author named 'Berry' was highly regarded. It did not have too much sugar in recipes. Book is still available, but now very old, and no doubt superseded by more up to date books/tastes.
Do not, in general brew these days, though I still do some wines, but this is really tied to using excess fruit from garden.