Parlo del mio progetto con il mio amico.

Because del is the contraction of di + il.

• di = of/about
• il = the
• del = of the / about the

The verb parlare di means to talk about, and progetto is a masculine singular noun, so it normally takes il:

• il progetto = the project
• parlo del progetto = I talk about the project

Since mio progetto also includes the article, it becomes:

• del mio progetto = about my project

So di mio progetto would sound incomplete and ungrammatical here.

Because parlare con qualcuno means to speak/talk with someone.

In this sentence:

• parlo di... = I talk about...
• con il mio amico = with my friend

So the sentence has both:

• the topic of the conversation: del mio progetto
• the person you are talking with: con il mio amico

This is a very common pattern in Italian:

• Parlo di musica con Luca. = I talk about music with Luca.
• Parliamo del film con i nostri amici. = We talk about the movie with our friends.

In Italian, subject pronouns are often omitted because the verb ending already tells you who the subject is.

• parlo = I speak / I am speaking
• parli = you speak
• parla = he/she speaks

So parlo already clearly means I talk.

You can say Io parlo, but it is usually only used for emphasis or contrast, for example:

• Io parlo italiano, lui parla inglese. = I speak Italian, he speaks English.

In a neutral sentence, Parlo del mio progetto... is more natural.

Parlo is the first person singular present tense of parlare.

• parlare = to speak / to talk
• parlo = I speak / I talk / I am speaking

Italian present tense often covers both the simple present and the English present progressive, depending on context.

So Parlo del mio progetto can mean:

• I talk about my project
• I’m talking about my project

The basic conjugation is:

• io parlo = I speak
• tu parli = you speak
• lui/lei parla = he/she speaks
• noi parliamo = we speak
• voi parlate = you all speak
• loro parlano = they speak

In Italian, possessive adjectives like mio, tuo, suo usually go together with a definite article.

So you normally say:

• il mio progetto = my project
• il mio amico = my friend
• la mia casa = my house

This is different from English, where my appears without the.

A very important exception: with singular family members, Italian usually omits the article:

• mio padre = my father
• mia sorella = my sister

But amico is not a family member, so the article stays:

• il mio amico

Literally, con il mio amico means with my friend.

With parlare, Italian often uses con where English may say either with or sometimes simply to, depending on the situation.

So:

• Parlo con il mio amico can mean I’m talking with my friend
• in natural English, that might also be expressed as I’m talking to my friend

But grammatically, Italian chooses con here.

Yes, absolutely.

Both of these are natural:

• Parlo del mio progetto con il mio amico.
• Parlo con il mio amico del mio progetto.

The meaning is basically the same: I’m talking with my friend about my project.

The difference is mostly one of focus or style:

• Parlo del mio progetto... puts the topic first
• Parlo con il mio amico... puts the person first

Italian word order is often more flexible than English, as long as the sentence remains clear.

Yes, progetto is masculine singular.

You can tell from the article and adjective agreement:

• il mio progetto

Here:

• il = masculine singular article
• mio = masculine singular possessive
• progetto = masculine singular noun

A plural version would be:

• i miei progetti = my projects

So the sentence shows agreement between the noun and the words around it.

Because both progetto and amico are masculine singular nouns.

The possessive adjective mio changes to match the gender and number of the noun:

• il mio progetto = my project
• la mia idea = my idea
• i miei amici = my friends
• le mie idee = my ideas

So in your sentence, both nouns use the masculine singular form mio.

Yes, del is written as one word because it is a standard contraction of di + il.

It is pronounced roughly like dehl.

Italian commonly combines certain prepositions with articles:

• di + il = del
• di + lo = dello
• di + la = della
• di + i = dei
• di + gli = degli
• di + le = delle

So del mio progetto follows a very common Italian pattern.

Very often, yes.

Parlare di is a standard way to express the topic of speech:

• Parlo di sport. = I talk about sports.
• Parliamo del libro. = We’re talking about the book.

But context matters. Sometimes parlare di qualcosa can also mean to discuss something or to mention something.

In your sentence, the meaning is straightforward:

• Parlo del mio progetto = I’m talking about my project

So a useful pattern to remember is:

• parlare di + topic
• parlare con + person