You have the "não" particle, so, it's a verb. "não como" = "don't eat", as a whole. If you use "como" for "as", it makes no sense here: I don't as cheese.
The software is correct, it means both, but according to the context (as for all the "hints", they are not all possible, you have to pick the good one)
Your sentence doesn't have a main verb (comer = eat), and you should have used the conjugation of "to do" (the auxiliary verb) that matches the subject - I do (not).
- Eu não como queijo. I don't [verbo auxiliar, conjugado na pessoa e tempo certos, mais partícula negativa not/n't] eat [verbo principal no infinitivo sem "to"] cheese.