Puedo acreditar la compra con el número de pedido del correo.

In Spanish, subject pronouns are often omitted because the verb form already shows who the subject is.

• puedo = I can
• so yo is not necessary

You could say Yo puedo acreditar la compra..., but it usually sounds more natural without yo unless you want emphasis, contrast, or clarification.

For example:

• Puedo acreditar la compra... = neutral
• Yo puedo acreditar la compra, pero él no. = emphasis/contrast

Puedo is the 1st person singular present tense of poder.

• poder = to be able to / can
• puedo = I can / I am able to

This verb is irregular:

• yo puedo
• tú puedes
• él/ella puede
• nosotros podemos
• vosotros podéis
• ellos pueden

Notice the stem change o → ue in most forms, but not in nosotros and vosotros.

Here, acreditar means something like:

• to prove
• to verify
• to show as evidence
• to demonstrate officially

It is a bit more formal than some other verbs learners may know.

Depending on context, Spanish might also use:

• demostrar
• comprobar
• justificar

So acreditar la compra sounds like to prove/verify the purchase, especially in a customer service or administrative context.

Spanish often uses the definite article where English might not.

• la compra = the purchase

Even if English might say something like prove purchase, Spanish normally prefers acreditar la compra.

This is very common in Spanish:

• cerré la puerta = I closed the door
• me duele la cabeza = my head hurts
• acreditar la compra = prove the purchase

So the article is completely natural here.

Con here means with or by using.

So:

• con el número de pedido = with the order number / using the order number

It shows the means or tool used to prove the purchase.

Similar examples:

• Pagué con tarjeta. = I paid with a card.
• Lo abrí con una llave. = I opened it with a key.
• Puedo justificarlo con este documento. = I can justify it with this document.

Número de pedido means order number.

Breakdown:

• número = number
• pedido = order

In shopping contexts, pedido is the usual word for an order you place with a shop or company.

A learner might wonder about orden, but orden is not usually the normal word for a purchase order in everyday shopping Spanish. In this context:

• pedido = customer order / purchase order
• orden often means command, arrangement, orderliness, or is used in some more specific contexts

So número de pedido is the most natural expression here.

Because de + el contracts to del in Spanish.

So:

• de el correo → del correo

This contraction is required in normal Spanish.

The only common exception is when El is part of a proper name:

• de El Escorial (not del Escorial when the official name is meant)

But in your sentence, correo is just a normal noun, so del correo is correct.

In modern everyday Spanish, especially in this kind of context, correo very often means email, although literally it can also mean mail/post.

Here, because the sentence mentions an order number, the most likely meaning is:

• the order number from the email

If you wanted to be extra explicit, you could say:

• del correo electrónico

In Spain, people very commonly shorten correo electrónico to just correo when the context is clear.

It most naturally connects to el número de pedido.

So the structure is:

• Puedo acreditar la compra
• con el número de pedido
• del correo

That means: the order number from the email is what is being used to prove the purchase.

In other words, the most natural reading is:

• the order number in/from the email

not:

• the purchase of the email

Spanish often stacks noun phrases like this, and context tells you what belongs together.

It is understandable and fairly natural, but it does sound a bit formal or administrative, mainly because of acreditar.

In customer service, claims, returns, or official situations, it fits well.

A more everyday version might be:

• Puedo demostrar la compra con el número de pedido del correo.
• Puedo comprobar la compra con el número de pedido del correo.
• Puedo justificar la compra con el número de pedido del correo.

So the original sentence is fine, but it has a slightly formal tone.

Yes, Spanish word order is somewhat flexible, but the original order is very natural.

Original:

• Puedo acreditar la compra con el número de pedido del correo.

You could also say:

• Con el número de pedido del correo, puedo acreditar la compra.

This version puts emphasis on how you can prove the purchase.

But for a neutral statement, the original sentence is probably the best choice.

Yes. In Spain, people often use both:

• correo
• correo electrónico
• email
• sometimes imeil in informal speech/spelling imitation

All are understandable, but the most standard written forms are:

• correo electrónico
• correo
• email

So these are all possible:

• ...del correo
• ...del correo electrónico
• ...del email

The choice depends on tone:

• correo electrónico = most explicit
• correo = natural when context is clear
• email = very common and modern