"I make dinner" is different than "I'm making dinner. If you say "Every night, I MAKE DINNER," that doesn't mean that you're making it right then.
I make dinner = Hago la cena I'm making the dinner = Estoy haciendo la cena
However,"I make the dinner", should definitely be correct, and if Duolingo says you're wrong, then you need to report your problem.
Hope this helped!
Because Spanish verbs are conjugated fully (with different endings) so the subject pronoun is not strictly necessary; it can be fully understood from the verb itself, unlike in English. In fact, native speakers might find it a bit odd if you kept using 'yo' over and over again in conversation. It's just repetitive of information the listener already has.
Having said that, the inclusion of 'yo' can be used to signal emphasis: two people are fighting over the check in a restaurant, one says: "No. Pago yo." (No. I'll pay). In this case the presence of 'yo' adds emphasis where the speaker wants it. I inverted the word order and, because it's not normal, it also works to emphasize the point.
This can be confusing sometimes. I had this phrase twice. Once as a translation with Yo an the begining where I typed I make dinner and scored wrong, immediately followed by type what you hear which i typed correctly as Hago la cena and was given the translation of I make dinner
I'm not sure I completely understand what happened, but from a Spanish grammar perspective, you don't NEED to have the personal pronoun in there, the conjugation implies it for you. You CAN use it if you want, but if you don't feel like it, no sweat. You can also use it to add emphasis to what you're saying.
Like this :) The present progressive isn't used so much in Spanish as it is in English. You can nevertheless say "Estoy haciendo la cena" (also, in place of "hacer", you can also use "cocinar" or "preparar"), but this is not used so often in Spanish, hopefully this makes sense and is a help :)
It is precisely for the reason that the present progressive is used perhaps even more frequently in English than the "simple" present (don't know what to call the "I make dinner" construction) that "I'm cooking dinner" is not only correct but much more idiomatic English. "I make/cook/prepare dinner" sounds like my friend recently visiting from Germany who always uses this form of the present and therefore sounds like exactly like that: a foreigner or person who's native language is not English. Clearly Duolingo, in the interest of providing idiomatic translations, should at least offer the present progressive alternative rather than call it wrong. It's current approach makes neither grammatical or pedagogical sense.