I don't want to discourage you but I think that it will be difficult to find scholarships for a Bachelor's degree. There are more opportunities for Master's and even more for Ph. D. and Post Doc positions. However, there are four main channels to search for funding. It is rare to find all kinds of funding on one single website/database.
The first one is at national/bilateral level, i.e. through your national Ministry of Education and/or Ministry of Foreign Affairs as well as the German cultural institute or national foundations which may administer scholarships on its behalf.
The second level is programs launched by the German government, e.g. DAAD https://www.daad.de/deutschland/stipendium/datenbank/en/21148-finding-scholarships/ or similar portals/initiatives http://research-in-germany.de/dachportal/en.html.
Third, look at the regional (state) initiatives, e.g. Study in Bavaria https://www.study-in-bavaria.de/
You can also explore universities one by one (for instance in a certain city or/and field) - there are many scholarships which are announced only on faculty pages, sometimes only in German; search for funding through learned societies http://www.scholarly-societies.org/ or foundations http://www.dw.de/focus-scholarships-and-funding-for-international-students-in-germany/a-6065777.
Funding for each of these options could be found on general scholarship websites (e.g. http://scholarship-positions.com/) or niche websites (e.g. humanities - http://www.h-net.org/announce/group.cgi?type=Funding; natural science - http://www.nature.com/naturejobs/science/) but the best strategy would be to do your own research and find a good program - see https://www.hochschulkompass.de/en/degree-programmes/suche.html.