One of the issues with learning vocabulary at A level is that so much is dependent on context. Of course you can find lists of specialist vocabulary regarding the different topic areas, but the generalist vocabulary that is required is a rather different thing and I'm not sure that anki or quizlet will actually be very helpful. You also need to be absolutely sure about what, exactly, is a noun, an adjective, an adverb, a preposition, a conjunction, etc.
Here are just a few random examples for French, but the same would apply for other languages.
fier - the (reflexive) verb: means to trust; the adjective: means proud.
fût - this is the imperfect subjunctive of "être", or as a noun, it means a barrel.
or take a word like moins:
moins de / moins que - both mean "less than" but are used in different contexts
au moins / du moins - both mean "at least" but are used in different contexts
à moins de / à moins que - both mean "unless" but are used in different contexts
le moins / le moindre - both mean "the least" but are used in different contexts
and I could go on...
To some extent, you will find that you absorb some of this as you go along. But I really would recommend that you go into your A levels with some understanding of basic grammatical concepts and that, when you learn new vocabulary, you automatically add information like: noun, verb, adjective, adverb etc. For nouns, if you're learning a language that uses different genders (like French, Spanish, Italian or German), make sure you learn the gender for any new nouns; it's a real nuisance having to learn these as an afterthought.