Si tu veux, je peux t’accompagner à la pharmacie avant de rentrer à la maison.

After si when you are stating a real or possible condition, French normally uses the present tense, not the future or the conditional.

So:

• Si tu veux, je peux... = If you want, I can...

Not:

• Si tu voudras...
• Si tu voudrais...

This is a very common French pattern:

• Si tu as le temps, on part maintenant.
• Si tu viens, je serai content.

A useful rule is: after a conditional si, avoid the future and the conditional.

Je peux makes the offer sound direct and natural: I can go with you.

Je pourrais is also possible, but it sounds a little more tentative, softer, or more hypothetical:

• Je peux t’accompagner = straightforward offer
• Je pourrais t’accompagner = I could accompany you

In everyday speech, je peux is very common for friendly offers, especially with Si tu veux at the beginning.

T’ is the short form of te, meaning you.

Before a vowel sound, te becomes t’:

• te accompagner → t’accompagner

So:

• je peux t’accompagner = I can accompany you

This is called elision.

In French, when you have a conjugated verb plus an infinitive, the object pronoun usually goes before the infinitive if it belongs with that infinitive.

Here:

• je peux = I can
• accompagner = to accompany
• t’ is the object of accompagner

So French says:

• je peux t’accompagner

not:

• je te peux accompagner

This is the same pattern as:

• Je vais te voir
• Je veux lui parler
• Je peux les aider

Yes. Accompagner quelqu’un means to accompany someone, and then the destination is introduced with a preposition such as à.

So:

• accompagner quelqu’un à la pharmacie
• accompagner quelqu’un au médecin
• accompagner quelqu’un chez le dentiste

The person comes directly after accompagner, with no preposition:

• t’accompagner

Then the place is added:

• à la pharmacie

In French, destinations usually take an article:

• à la pharmacie
• à la banque
• au supermarché

So French does not normally say just à pharmacie.

The article la is there because pharmacie is a feminine singular noun:

• la pharmacie

And à + la stays à la.

After avant, when the next verb is in the infinitive, French uses de:

• avant de rentrer
• avant de partir
• avant de manger

So avant de + infinitive is the normal pattern.

That is why:

• avant de rentrer à la maison = before going home

Use avant de + infinitive when the subject is the same or understood generally.

Use avant que + subjunctive when there is a different subject.

Compare:

• Je vais finir avant de partir.
  Same subject: I finish, then I leave.

• Je vais finir avant que tu partes.
  Different subject: I finish before you leave.

In your sentence, avant de rentrer is used because French treats the subject of rentrer as understood from context.

The subject is implicit, not stated directly.

From context, it usually means:

• before you go home
• or before we go home

French often leaves this unstated with an infinitive when the meaning is obvious from the situation.

If the speaker wanted to be more specific, they could say:

• avant de rentrer chez toi = before you go home
• avant de rentrer chez moi = before I go home
• avant qu’on rentre à la maison = before we go home

Rentrer is very natural when talking about going back home or returning home.

So:

• rentrer à la maison = go back home / head home

Aller à la maison is grammatically possible, but it sounds less idiomatic in many everyday situations. A native speaker would more naturally say:

• rentrer à la maison
• retourner à la maison

Among these, rentrer à la maison is especially common in conversation.

À la maison means home in a general sense.

It does not specify whose home it is. That can be useful when the context already makes it clear.

By contrast:

• chez moi = to my place / home
• chez toi = to your place / home
• chez nous = to our place / home

So:

• rentrer à la maison = go home
• rentrer chez moi = go to my place / go home to my house

French often uses à la maison when the exact owner of the home is not important.

Yes. Tu shows the sentence is informal, singular, and used with someone the speaker knows well.

A more formal or plural version would be:

• Si vous voulez, je peux vous accompagner à la pharmacie avant de rentrer à la maison.

So:

• tu / t’ = informal singular
• vous = formal singular or plural

This is a very common change in French, and the rest of the sentence stays mostly the same.

The te becomes t’ because of elision, and it links smoothly into the next word.

A rough English-friendly guide would be:

• t’accompagner ≈ ta-kon-pa-nye

More exactly, the ending -gner sounds like nyay or nyeh depending on accent, not like English gner.

So the whole part:

• je peux t’accompagner

is pronounced roughly like:

• zhuh puh ta-kon-pa-nye

The important thing for learners is:

• t’ is pronounced together with accompagner
• the gn sound is like the ny sound in canyon