“Your Holiness", “Your eminence", “Your excellency", are ways to address a Pope, a Cardinal, and a Bishop respectively. These titles, especially “Your Holiness", would ordinarily lead people to think that maybe those who bear these titles do not sin at all. Some time ago I corrected the impression that the Pope does not sin since he is “Infallible".
The Pope, like every other Christian sins (not necessarily mortally) from time to time and needs the redemptive office of the Church for freedom and growth. The Pope as well as any other Bishop, confesses to any clergy he chooses as his confessor and spiritual director. It could be a priest or a bishop. It’s worth noting that the Pope or a bishop or any serious Catholic does not necessarily need to wait to commit a mortal sin to go to confession. Most Popes go to confession daily and it’s safe to believe that they confess simple day to day neglects and imperfections not necessarily mortal or even wilful venial sins. A person CAN live a holy life free of mortal sins, indeed this is what the Church exhorts us to do and one of the ways to get there is to frequently confess even our venial sins to our confessor/spiritual director.
Infallibility as a Papal charism means that He cannot err while defining Faith, that whenever he speaks “ex cathedra”, i.e. from the chair of Peter as Vicar of Christ and Shepherd, that the Spirit of Christ DOES NOT ALLOW HIM TO MAKE MISTAKES IN DEFINING THE FAITH OF THE WHOLE CHURCH. This does not mean he cannot sin or even make erroneous pastoral judgement, he sure can.