Tengo hambre hoy.

Because Spanish usually expresses hunger with tener + a noun, not estar + an adjective.

• tener hambre = literally to have hunger
• English says I am hungry
• Spanish says I have hunger

This is a very common pattern in Spanish:

• tener hambre = to be hungry
• tener sed = to be thirsty
• tener sueño = to be sleepy

So Tengo hambre hoy is the normal, natural way to say it.

Tengo is the first-person singular present tense form of tener.

• tener = to have
• tengo = I have

So:

• Tengo hambre = I have hunger → meaning I am hungry

Because the verb form already shows the subject, Spanish does not need yo here.

Spanish often leaves out subject pronouns when they are already clear from the verb form.

• Tengo already tells you the subject is I
• So (Yo) tengo hambre hoy and Tengo hambre hoy both mean the same thing

Usually, yo is omitted unless you want to:

• add emphasis
• create contrast
• avoid confusion

For example:

• Yo tengo hambre, pero ella no. = I’m hungry, but she isn’t.

In a simple sentence, leaving out yo is more natural.

Because the normal expression is simply tener hambre, not tener la hambre or tener un hambre.

This works like a fixed expression:

• tener hambre = to be hungry
• tener sed = to be thirsty
• tener miedo = to be afraid

So in this sentence, no article is needed.

Sometimes you may hear something like tener mucha hambre = to be very hungry, where a modifier is added, but still no article:

• Tengo mucha hambre hoy.

Hambre is feminine.

That can be confusing because with the singular definite article it often appears as el hambre, not la hambre. That happens because the noun begins with a stressed a sound, and Spanish avoids la hambre for sound reasons.

But the noun is still feminine, which you can see in adjectives:

• el hambre extrema
• mucha hambre

In your sentence, though, this issue does not appear, because there is no article after tener:

• Tengo hambre hoy.

Yes, you can, and it means I’m hungry today, but Tengo hambre hoy is more common and more natural in everyday Spanish.

Compare:

• Tengo hambre hoy. = very common, everyday way
• Estoy hambriento hoy. = understandable, but less common in ordinary conversation

Also, hambriento/hambrienta works like a regular adjective, so it changes with gender:

• Estoy hambriento. = said by a man
• Estoy hambrienta. = said by a woman

For most learners, tener hambre is the safer default.

Yes, hoy can move.

All of these are possible:

• Tengo hambre hoy.
• Hoy tengo hambre.

Both are natural. The difference is mostly one of emphasis:

• Tengo hambre hoy puts the time expression at the end
• Hoy tengo hambre emphasizes today

What sounds less natural is placing hoy between the verb and hambre:

• Tengo hoy hambre — grammatical, but not the usual everyday order

So the sentence you have is completely normal.

No. In standard Spanish, h is silent.

So:

• hambre sounds roughly like AHM-breh
• hoy sounds roughly like oy

A couple more pronunciation notes:

• In most of Latin America, hoy sounds like oy
• Tengo begins with a strong t
• The r in hambre is a single tap, not a strong rolled rr

Just put no before the verb:

• No tengo hambre hoy. = I’m not hungry today.

This is the standard way to negate a sentence in Spanish:

• Tengo hambre. → No tengo hambre.
• Tengo sueño. → No tengo sueño.

You can make it a question by changing the intonation in speech, and in writing by adding question marks:

• ¿Tienes hambre hoy? = Are you hungry today?
• ¿Tienen hambre hoy? = Are you all hungry today?

If you want to keep I, you could also ask:

• ¿Tengo hambre hoy? = Am I hungry today?

That is grammatically correct, though less common as a real-life question unless you are being humorous or uncertain.

Yes. Tengo is present tense, and in English it is usually translated naturally as I’m hungry today rather than the more literal I have hunger today.

Spanish present tense often covers what English expresses with am/is/are in these kinds of idiomatic expressions.

So:

• Tengo hambre hoy = I’m hungry today
• literally: I have hunger today

The literal meaning helps explain the grammar, but the natural English meaning is the one you should use.