In fact I would encourage you to start this way as there is much to learn before you need to use the parts that cost money. Power BI desktop is the place where you will do all the primary work. This part is totally free and Microsoft have guaranteed that this will never change.
If you use Windows 10 OS or greater, you can download it from: Get Power BI Desktop – Microsoft Store Otherwise this is place for downloading: Download Microsoft Power BI Desktop from Official Microsoft
When you open Power BI Desktop you will be greeted by a pop up box, shown below. Just close it and you’re good to go. You are now ready to get started with Power BI. 😊