They Communist Party of Britain seek to reform what they call the “state-monopoly capitalism” that they say exists today into the sort of state capitalism that exists in China which they falsely believe is “socialism”.
This is to be achieved by a united front of all non-monopoly elements, including non-monopoly capitalists, to elect a leftwing reformist government. They work to achieve this. This is combined with praise for China and nostalgia for the USSR.
Since the fall of the USSR, whose foreign agents they were, they have really had no reason to exist. But unfortunately they still do, sowing confusion as to what socialism is.
The truth that they are anti-socialists is confirmed by their practice.