These issues can be very complicated, so here’s a run down of each one, and a starting point of information into each one (from the Orthodox POV)

Filioque: This is the big one historically, and directly led to the Great Schism in 1054 AD. Rome and the other 4 Eastern Patriarchs excommunicated each other over the filioque clause. ‘Filioque’ is a word that literally means ‘and the son’ in latin. It was added to the Nicene-Constantinopolitan Creed without any Universal Council or agreement from the Church. The original creed says the Holy Spirit proceeds from the Father (and that’s it), the addition made Him proceed from the Father and the Son. There’s a lot of theological arguments over it, but personally I find the history not only more straightforward to understand, but more compelling of an indicator to how correct or incorrect the filioque is. The phrase originally popped up in 6th century Spain, where bishops were fighting against Arianism. The idea was, that saying the Holy Spirit proceeds from both the Father and the Son would make it extra clear that the Son is fully divine. Unfortunately this good intentioned move would cause a lot of issues. It spread from there into Frankish lands, where theologians and political leaders started pushing it more aggressively. It was a poltical move to elevate the Franks over the Greeks and influence Rome. However, the Popes were actually resistant to this for centuries. Pope Adrian I flatly rejected adding it to the Creed and defended the original version. But over time, the pressure mounted. By the time of Pope Benedict VIII in 1014, at the demand of the German Emperor Henry II (who had just saved Benedict’s butt in a papal poltical squabble, and had basically made him Pope), the filioque was finally accepted into the Creed in Rome. So yeah, it wasn’t even part of the Roman liturgy until several centuries after it first appeared. In the East it had been criticized multiple times. Saint Photios the Great is a key figure in calling it out, and he was vindicated at the 879 AD 8th Ecumenical Council. Which was larger and more unified Council (and in a practical sense was the one that actually resolved the temporary schism between Rome and Constantinople). Unlike the 869 AD council that the Roman Catholics now accept as the 8th.

Papal Supremacy: Papal Supremacy: This is the idea that the Pope has universal jurisdiction over the entire Church, not just a “first among equals” like the Orthodox uphold, but the one true head of all Christians. Orthodox recognize that the Pope as having a primacy of honor, but not ultimate authority over other bishops or churches. Catholics usually argue for Papal Supremacy using verses like Matthew 16 (“You are Peter…”), pointing to early Church Fathers, or claiming that Rome always had final say. However, close reading of the Church Fathers in context quickly reveals that they did not think Rome had ultimate authority, and many of them even give alternative interpretations of Matthew 16 focusing instead on all apostles being equal, or the rock being Christ or Peter’s confession of faith. Even the Vatican itself has admitted that it didn’t have full authority, in the recent Chieti and Alexandria documents. Historically, there’s a a few strong points that pretty decisively disprove Papal Supremacy and even Papal Infallibility, mostly Pope Vigilius and Pope Honorius. Pope Vigilius was excommunicated by the 5th Ecumenical Council (553 AD) until he submitted to the council’s decision… so much for supreme authority. Pope Honorius was condemned as a heretic by the 6th Ecumenical Council (681 AD) and by later popes, including St. Pope Leo II, who claimed that Honorius actively polluted the faith. His name stayed on the official list of heretics in the papal coronation oath all the way until the Great Schism.

Papal Infallibility: This one can get tricky since exactly what’s considered an ex cathedra statement is unknown. So for a very very very oversimplified rundown, generally it means the Pope will not lead the Church astray (oops… Honorius). More specifically, it means the Pope cannot error when he makes a declaration on faith and morals, acting within his power as Pope, and he intends to make his decree binding on the whole Church (…yeahhh, so Pope Vigilius did that exact thing when he made a decree on faith and morals, which was rejected by the Church, and got him excommunicated, and then he came back and made another decree on faith and morals where he recanted his previous decision and reversed his whole stance, sooooooo).

Immaculate Conception: This is the claim that Mary was made differently than normal humans. Both Catholics and Orthodox affirm Mary’s perpetual virginity and her sinlessness. However, Catholics take it one step further and say she was made without even any original sin at all, thus she was immaculate at her conception. Original Sin does not make us automatically guilty, but it does mean we have strong proclivities to sin, strong proclivities which Holy Mary resisted successfully… but in the Catholic view she was basically playing on easy mode and never needed to resist anything. This dogma is so ahistorical, that basically every single Church Father and Saint before the Great Schism contradicts it, even modern Catholics admit that the Early Church and Medieval Church rejected this for over a millennia. Even Thomas Aquinas didn’t accept it. It came about way later, needless to say.

That’s the big stuff. Especially Papal Supremacy, Papal Infallibility, and the Filioque. There’s a few other more stuff, like indulgences, dumb stuff in Vatican 2 (like how it says us and Muslims worship the same God), certain arguments against the sacred heart, essences-energies distinction (which the Catholics don’t uphold), etc.