The most important aspect of creating any database is to get the data
structure right, so here's a starting point:
http://www.databaseanswers.org/data_models/hospital_admissions/index.htm
Once you have understood the one-to-many relations, creating the tables with
primary keys and foreign keys, and created the relationships between them,
you can then go on to creating the forms as the interface to add, edit and
delete the data stored in those tables, and the code to validate and respond
to the data, followed by the queries and reports that produce meaningful
hard copies for everyone.
Then comes the process of documenting how it works, testing, and final
debugging, followed by a period where your system is run in parallel with
whatever procedures the hospital currently has in place until it is all
verified as working correctly.
Before you begin any of that process, you will need to complete an analysis
of what the software needs to do, so that you do not get part way through
the development process and discover there is a gaping black hole in your
design.