Hey!
Please go through the following points and links to get a clear idea about studying science in Germany:

• There are several ways you can attend a university in Germany: as an undergraduate (Bachelor's degree), as part of a semester or year abroad from India, as a doctoral student.
• Some universities specialise in a particular subject area and are called technical universities (Technische Universität, TU) or colleges of education (Pädagogische Hochschule, PH).
• At Fachhochschulen and Hochschulen für angewandte Wissenschaften (Universities of Applied Sciences) the emphasis is more on practical training in a subject.
• Dual universities combine academic studies and vocational training.
• During a bachelor's degree programme, you acquire basic knowledge of a subject over six to eight semesters. This also consist of two subjects or a major and two minor subjects.
• During a master's programme, you can deepen and extend your knowledge or specialise in a particular field over two to four semesters.
• Some master's degree programmes are offered in English. If you want to study in English, you can inquire at the International Office at your chosen university or search the DAAD Online Database.
• During your doctoral studies, you write a research paper on a specific subject (dissertation or doctoral thesis). The duration of the doctorate depends on the research topic, most are two to five years. The doctoral studies end with the award of a PhD.
• There are two types of doctorates: in the traditional model, you work independently on your dissertation and will be supervised by a professor from the faculty.  if you want to study for a doctorate, you will need to find a PhD supervisor beforehand. Alternatively, you can have a fixed period of three years during which you work on your dissertation with several supervisors. You need to clarify beforehand which university and which research focus are available for your topic.
• https://www.study-in-germany.de/en/plan-your-studies/find-programme-and-university/
• https://www.daad.de/deutschland/studienangebote/international-programmes/en/

Hope it helps!