English has one word for 'the'. Italian has seven — il, lo, la, l', i, gli, le — because articles agree with the noun's gender and number, and adapt to the sound that follows. It looks intimidating; it is actually one of the most regular systems in the language.
The core pattern
- il libro → i libri (masculine, standard)
- la casa → le case (feminine)
- lo studente → gli studenti (masculine before s+consonant, z, gn…)
- l'amico → gli amici (before vowels)
Il caffè è pronto. La colazione è sul tavolo.
One mindset shift helps more than any rule: learn every noun together with its article. Never memorize 'tavolo' — memorize 'il tavolo'. Your ear will do the grammar for you.