This Coursera course will be a good place to start: https://www.coursera.org/learn/healthcare-medical-technology
Essentials of Pharmacoeconomics by Karen L. Rascati is a good place to learn some basic concepts.
Decision Modelling for Health Economic Evaluation is a good book to learn modelling. There are Excel exercises in the book.
Cost Effectiveness Modelling for Health Technology Assessment is another book for modelling. In my opinion, the exercises in this book are easier than the one above.