Becoming an astronaut with Cambridge degree

If I study Msci Natural Sciences at Cambridge University or other universities, focusing mainly on biological sciences including in the admissions assessment choice with developmental biology and molecular ecology module focused choices, will I be able to meet basic qualifications as an astronaut at ESA and other space programs?

ESA are not currently hiring astronauts. However, during their last astronaut selection (2021-22) they stated that the qualifications were as follows:

"What qualifications are needed to apply?
Applicants must have a minimum of a Master’s degree from a recognised academic institution in natural sciences (including physical sciences; Earth, atmosphere or ocean sciences; biological sciences), medicine, engineering or mathematics/computer sciences, with at least three years of professional experience after graduation. This could include working in a lab, conducting research in the field or working in a hospital. A PhD or equivalent degree, or additional Master’s degrees in the aforementioned subject areas, are considered an asset.

A degree as Experimental Test Pilot and/or Test Engineer from an official Experimental Test Pilot School is also accepted. These institutions include EPNER (France), ETPS (England), USAF TPS (US Air Force) and USNTPS (US Navy). Commercial school NTPS is also included here. Candidates with these qualifications will be assessed on a case-by-case basis and may be asked to provide a copy of their diploma or statement from their school regarding the level of the qualification."

The degree which you have described would appear to meet those criteria. Note that during the 2021-22 astronaut selection they had just two vacancies: "Astronaut and Astronaut (with a physical disability)". You might also like to read the Astronaut Application Handbook.