Il pescivendolo mi ha consigliato del salmone fresco per la cena.

Pescivendolo means fishmonger or fish seller.

It is built from:

• pesce = fish
• vendere = to sell

So pescivendolo is literally a person who sells fish. It is a masculine singular noun. The feminine form is pescivendola.

Italian normally uses the definite article when talking about a specific person or thing.

So:

• il pescivendolo = the fishmonger

In this sentence, we are talking about a particular fishmonger, not fishmongers in general. Leaving out il would sound unnatural in standard Italian.

Mi means to me.

So:

• mi ha consigliato = recommended to me

It is an object pronoun, and in Italian these short pronouns usually go before the conjugated verb or before the auxiliary in a compound tense.

That is why you get:

• mi ha consigliato not
• ha consigliato mi

Ha consigliato is the passato prossimo, a very common Italian past tense used for completed actions.

It is formed with:

• ha = has
• consigliato = past participle of consigliare = to recommend / advise

So literally it is something like:

• has recommended

In natural English, you would usually translate it as:

• recommended

This tense shows that the recommendation happened as a completed event.

The h in ha is there to distinguish it from a.

• ha = has from avere
• a = to

The h is not pronounced, but it is very important in writing.

So:

• mi ha consigliato = he recommended to me
• mi a consigliato would be incorrect

Del salmone means some salmon.

Here del is a partitive article, used for an unspecified quantity of something.

• del = di + il
• del salmone = some salmon

Compare:

• del salmone = some salmon
• il salmone = the salmon, a specific salmon
• un salmone = a salmon, usually one whole salmon

Because food is often treated as an uncountable substance, Italian commonly uses the partitive here.

In Italian, adjectives can come before or after the noun, but after the noun is very common when the adjective is describing a real, distinguishing quality.

So:

• salmone fresco = fresh salmon

Here fresco tells you what kind of salmon it was. It is a straightforward descriptive adjective, so placing it after the noun is the most natural choice.

Putting it before the noun would sound more marked or literary in this case.

Because salmone is masculine singular, the adjective must agree with it.

So:

• salmone = masculine singular
• fresco = masculine singular

Agreement examples:

• salmone fresco = masculine singular
• trota fresca = feminine singular
• gamberi freschi = masculine plural
• sarde fresche = feminine plural

Even though del salmone means some salmon, the noun itself is still grammatically singular here.

Per la cena means for dinner or more literally for the dinner meal.

Italian often uses the definite article with meals in expressions like this, especially when referring to a specific occasion or the evening meal in general context.

So:

• per la cena = for dinner

This is very natural Italian. In other contexts, you may also see expressions like:

• a cena = at dinner / for dinner

But in this sentence, per la cena fits the idea of recommending something for that meal.

Here, to recommend is usually the best way to understand it.

With food, products, or choices, consigliare often means:

• to recommend
• to suggest

So:

• Il pescivendolo mi ha consigliato del salmone fresco
  is more naturally:
• The fishmonger recommended some fresh salmon to me

Using advise in English is possible in a broader sense, but for food and purchases, recommend sounds much more natural.

A little, yes, but the original word order is the most neutral and natural.

Standard order here is:

• Il pescivendolo = subject
• mi = object pronoun
• ha consigliato = verb
• del salmone fresco = thing recommended
• per la cena = purpose

So the sentence flows very naturally.

You might also hear variations for emphasis, such as:

• Per la cena, il pescivendolo mi ha consigliato del salmone fresco.

But the original sentence is the most straightforward version for normal conversation.