Azienda usually means company, business, or firm.
In this sentence, l’azienda is naturally understood as the company that might hire the speaker.
Depending on context, azienda can refer to:
Mi is the direct object pronoun meaning me.
Italian object pronouns normally come before a conjugated verb:
This is normal Italian word order. English puts me after the verb, but Italian usually puts mi before it.
Other similar pronouns are:
This is one of the most important grammar points in the sentence.
In Italian, when you talk about a real future condition, you normally use:
So:
Not:
This is similar to English, which also often uses the present after if:
not usually
Because it describes what the speaker will do if the condition is met.
Inizierò is the first person singular future simple of iniziare:
The structure is:
So the hiring is the condition, and starting on Monday is the future result.
In Italian, days of the week usually appear without an article when you mean a specific day:
So:
If you use an article with a day of the week, it often suggests habitual meaning:
So in your sentence, no article is used because it refers to one specific Monday.
The comma is very normal here because the if-clause comes first:
It helps separate the condition from the result.
If the order is reversed, the comma is often less necessary:
So the comma is standard and natural in the original sentence.
Not in this sentence.
With a normal real condition like this, Italian uses the indicative, not the subjunctive:
The subjunctive is not the standard form after se in this kind of sentence.
A learner often expects the subjunctive because the event is uncertain, but uncertainty alone does not automatically trigger the subjunctive after se.
It is neutral and completely natural.
Nothing in the sentence is especially informal or especially formal. You could use it in:
If you wanted to sound a little more explicit, you could add a lavorare:
But the original sentence is already perfectly good Italian.