There isn't a single, readily available figure for the total number of students graduating from UK universities each year. Data is collected and reported in different ways, sometimes including postgraduate students, sometimes not. Also, the number fluctuates slightly year to year.
To find the most up-to-date information, you'd need to consult official sources like the Higher Education Statistics Agency (HESA) in the UK. Their website provides detailed breakdowns of higher education statistics, including graduations, but requires navigating their data.