Learn Italian: Oggi vado alla posta e al supermercato. - Today I am going to the post office and to the supermarket.

Andare (to go) is a highly irregular verb. Instead of following the normal -are verb rules, the "I" form changes completely to vado (I go / I am going). You just have to memorize these special forms!

The English translation says "I am going", but isn't vado just "I go"?

In Italian, the simple present tense covers both. Vado can mean "I go" (a routine) or "I am going" (happening right now or later today). Italian doesn't require a separate "am going" structure for everyday actions like English does.

Why is it alla posta but al supermercato?

Both words mean "to the", but they must match the gender of the destination. Posta (post office) is feminine, so you combine the preposition a (to) with la (the) to make alla. Supermercato (supermarket) is masculine, so a + il (the) combines to make al.

Is it okay to keep the words separate and write a la posta?