Danas kuham grah, a sutra ću napraviti salatu od kupusa.

Croatian often drops subject pronouns when they are not needed, because the verb ending already shows who is doing the action.

• kuham = I cook / I am cooking
• ću napraviti = I will make

So ja is understood. You could say Ja danas kuham grah..., but that usually adds emphasis, like I am the one cooking.

It can mean both. Croatian present tense often covers both the English simple present and present continuous, depending on context.

So Danas kuham grah can mean:

• Today I’m cooking beans
• or more generally Today I cook beans

In this sentence, the most natural English meaning is usually Today I’m cooking bean stew / beans.

Croatian future tense is commonly made with:

• a form of htjeti used as a clitic: ću
• plus the infinitive: napraviti

So:

• ću napraviti = I will make

This is the normal future I construction in Croatian.

Yes, partly. Croatian verbs have aspect, which is very important.

• kuhati is imperfective: it focuses on the process, duration, or repeated action.
• napraviti is perfective: it focuses on a completed result.

Here that makes good sense:

• Danas kuham grah = the activity/process is happening today
• sutra ću napraviti salatu = tomorrow you will complete the action of making a salad

English speakers often need time to get used to this, because English does not organize verbs this way as strongly as Croatian does.

Sometimes, but napraviti is more natural here if you mean make/prepare and finish it.

• napraviti salatu = make a salad, with focus on the completed result
• praviti salatu = be making / make, with less focus on completion

In a sentence about tomorrow, Croatian often prefers a perfective verb like napraviti for a one-time completed action.

A often links two parts of a sentence while also showing a contrast or change of topic.

Here it means something like:

• Today I’m cooking beans, and/as for tomorrow I’ll make cabbage salad.

It is not a strong contradiction, so ali (but) would sound too strong.
And i (and) would just join the two ideas without that nice contrast between today and tomorrow.

Because grah is the direct object here, and for a masculine inanimate singular noun, the accusative is usually the same as the nominative.

So:

• nominative: grah
• accusative: grah

That is why you do not see a new ending.

Compare that with an animate masculine noun:

• pas = dog
• Vidim psa = I see the dog

There the accusative does change.

They are in different cases for different reasons.

• salatu is the direct object, so it is in the accusative singular
• kupusa comes after od, and od requires the genitive

So:

• salata → salatu
• kupus → kupusa

This is a very common pattern in Croatian:

• direct object → often accusative
• after certain prepositions, like od → genitive

Literally, od kupusa means of cabbage or from cabbage.

In natural English, here it is best understood as:

• cabbage salad
• or salad made from cabbage

Croatian often uses od + genitive to describe what something is made of or composed of.

It can mean either, depending on context.

In everyday Croatian, grah often means the bean dish, not just the raw beans. So in this sentence many speakers would understand something like:

• Today I’m cooking bean stew / a bean dish

That is very common with food vocabulary.

Croatian word order is fairly flexible, and speakers often put time expressions early in the sentence.

So:

• Danas kuham grah
• a sutra ću napraviti salatu od kupusa

sounds natural because it highlights when each action happens.

You could move things around, but this version is clear and idiomatic.

Yes. That is also a normal Croatian future form.

Both are possible:

• Sutra ću napraviti salatu od kupusa
• Sutra napravit ću salatu od kupusa is not the usual standard order
• Napravit ću salatu od kupusa sutra can work, but it changes the emphasis

The most standard and natural version here is sutra ću napraviti... because the clitic ću usually comes near the beginning of the clause, after the first stressed element.

Also, when the infinitive comes before ću, Croatian often shortens it:

• napraviti ću → usually napravit ću

Because Croatian does not have articles like English.

So nouns can appear without words like:

• a
• an
• the

Whether the meaning is definite or indefinite is understood from context.

So grah could mean:

• beans
• the beans
• some beans
• bean stew

depending on the situation. The same idea applies to salatu.