Power BI is a self-service (and enterprise) Business Intelligence (BI) tool that facilitates data acquisition, modeling, and visualization&;and the skills needed to succeed with Power BI are fully transferable to Microsoft Excel. There are three learning areas required to master everything Power BI Desktop has to offer: TheM Language, The DAX Language, and analysis. Super Charge Power BI clearly explains the necessary concepts while at the same time giving hands-on practice to engage the reader and help new knowledge stick. 
Matt Allington is a Microsoft Data Platform MVP that specializes in teaching and helping business users leverage the Power BI suite to achieve positive business outcomes.