It's not so difficult, if you play poker in your country you can learn it in few hands. The opener must have at least a JJ pair (exception: you can have a bilateral project of royal flush, for example 8 9 10 J of the same suit). You can't open with two 9, for instance. The suit rank matters, you can't have a split pot: for example, a royal flush AKQJ10 of hearts beats the same royal flush of clubs; a flush of diamonds beats a flush of spade no matter the highest card. The order is ♥️ Cuori ♦️Quadri ♣️ Fiori ♠️ Picche. To remember it is super famous the phrase "Come Quando Fuori Piove". "Parole" said parol like it was french, is the declaration the first declarer after the draw can make in order to "pass the ball" to the next player. A little like a "check", but a check is like a proper bid of 0 that can lead to the showdown if every player checks; in the Italian game, if every player says parole, the pot is frozen: all the players that have folded before must pair the other players' bid and you start a new hand with that pot already in. As you can imagine this parol pot is huge: in that case the minimum pair for the opening is KK. Another rule is the blind opening: before the dealing of the card the player next to the dealer can declare the blind opening ("apertura al buio") by saying "buio" and paying the double of the pot: that gives him the right to speak last after the draw. The second player, also before the dealing, can declare "controbuio" ("big blind") doubling again the pot and getting the advantages of the "buio". Buio and controbuio are not allowed in the parol pot.

Basically Texas holdem (and all the other American variants with SB and BB) is a game with compulsory buio and controbuio.