There's no shortage of possible majors in the life sciences: pre-med, microbiology, ecology, and biotechnology to name just a few. However, at least at some European universities, you're also welcome to forgo choosing a specific major. This allows you to mix and match courses as you please, perhaps to prepare yourself for a very specific, niche career.
Two of the primary reasons students are drawn to life sciences are a desire to perform their own groundbreaking research one day, or plans to go into the medical profession in some capacity. An undergraduate degree in life sciences makes both possible.
You'll need a fairly broad foundation to even get started, though. At a minimum, you'll need to know a little mathematics, chemistry, biology, genetics, and physics. After that, which will probably occupy at least your first two or three semesters, you can choose your own path with a general life sciences degree.