It sounds like you need help learning to use the Worship Tools programs. The first thing to understand is that there are 4 programs, each one designed for different purposes. I mainly know about Presenter, since my church doesn't need the other programs at this time. I believe that changing a song's key is done in Charts. The documentation for all 4 programs is at
https://www.worshiptools.com/en-us/docs. Scroll down on the left until you get to the program you want to learn about, and click on the subject you want to study. There are both written articles and tutorial videos. I recommend that you start at the top with the General information.
The free version is fully functional and quite adequate to learn from. Your church might need a paid version to get all the features you want, but you can learn much about the programs without spending a dime. And many churches operate quite well on the free version.
Remember, this is a User Forum. While Worship Tools representatives comment at times, most of the posts and comments are from fellow users who are trying to help other users.