Cuento hasta ochenta.

Because contar is a stem-changing verb in the present tense. Its o changes to ue in most forms:

• yo cuento
• tú cuentas
• él/ella cuenta
• nosotros contamos
• ustedes cuentan

So cuento is the correct yo form.

Here, cuento means I count.

It comes from the verb contar, which can mean different things depending on context, such as:

• to count
• to tell
• to narrate

In Cuento hasta ochenta, the phrase hasta ochenta makes it clear that cuento means I count, not I tell.

Spanish often leaves out subject pronouns because the verb ending already tells you who the subject is.

• cuento already means I count
• so yo cuento and cuento both mean the same thing

Adding yo is possible, but it is usually only used for emphasis, contrast, or clarity.

In this sentence, hasta means up to or until, but in natural English we usually translate the whole phrase as count to eighty.

With numbers, contar hasta + number is the normal pattern:

• contar hasta diez = count to ten
• contar hasta cien = count to one hundred

So hasta is the word Spanish uses in this structure.

Because after contar, Spanish normally uses hasta when talking about reaching a number in a count.

So the standard expression is:

• cuento hasta ochenta

Not:

• cuento a ochenta

If you want to show a range, you might say something like cuento de uno a ochenta for I count from one to eighty.

Because when Spanish uses a number after hasta in this kind of counting expression, it normally uses the bare number:

• hasta diez
• hasta veinte
• hasta ochenta

Adding el would usually change the meaning and make it sound more like the number eighty rather than simply counting up to that number.

A good approximate pronunciation for English speakers is:

• KWEN-toh

A few details:

• cu sounds like kw
• en sounds like en in ten, but cleaner and shorter
• the stress is on the first syllable: CUEN-to

So: KWEN-toh.

A good approximation is:

• oh-CHEN-tah

The stress is on the middle syllable:

• o-CHEN-ta

In Latin American Spanish, the ch sounds like the ch in chair.

Yes. Cuento can also be a noun meaning story or short story.

For example:

• un cuento = a story

Also, as a verb form from contar, cuento can mean I tell in some contexts.

So context matters:

• Cuento hasta ochenta = I count up to eighty
• Cuento una historia = I tell a story
• Leo un cuento = I read a story

Spanish present tense can cover both ideas depending on context.

So cuento hasta ochenta can mean:

• I count to eighty
• I am counting to eighty

If you want to strongly emphasize the ongoing action, Spanish can also use:

• Estoy contando hasta ochenta

But the simple present is very common and natural.

Yes, absolutely. It sounds natural in contexts like:

• practicing numbers
• describing what you are able to do
• giving instructions in a game
• talking about counting during an activity

For example:

• Cuento hasta ochenta sin equivocarme.
• Espera, cuento hasta ochenta.

So the sentence is short, correct, and natural.