"High Church" or "Anglo-Catholic" is a fairly large group within the Church of England. It means that you think that the rituals and ceremonies which have grown up over the last 2,000 years are a valid way of worshipping God and didn't really need to be "reformed." Sometimes fondly referred to as "bells and smells." (Lots of robes, chanting, incense, normally older translations of the Bible, etc.)
However, it's still C of E. As a Protestant group, Anglicans think that Roman Catholics have some pretty serious misunderstandings of the teachings of Jesus and the early Church about theology (and obviously RCs think the same about Protestants). For instance, most Anglicans think that a lot of the language about bread and wine etc is symbolic not literally true, and they disagree that the Pope is anything more than an important bishop. RC theology tends to maintain that a spiritual/metaphysical change happens when becoming a priest; Anglicans think that a priest is more a representative of the people as well as a minister of God (so the C of E has a 'bottom up' structure, with elected councils to represent congregations, as well as a 'top down' structure). There are also a lot of more subtle and obscure differences about how the two traditions understand the role of Jesus and how people are saved, and even which books count as being in the Bible.
Tldr; Anglicans (very) vaguely agree on what they believe, and that it's different to RC or Orthodox ("theology"), but the differ about how to express that ("ecclesiology"). You could set exactly the same lyrics to a classical operatic aria or a modern pop-song! Individual Anglicans find a church which fits their style.