ESRI is a large geospatial software company. They have long been the industry leaders in providing geospatial analysis software. Their products are not free. However, you can enroll in free massive open online courses (MOOCs) with them and have access to their software to work through the assignments for the duration of the course.
Miami University supports ESRI products including ArcGIS Pro, ArcMap, and ArcGIS Online through the Dept of Geography's GISci Computer Labs (SHD 132, 134). You can get more information about the products offered here - Miami University GIS Resources
Geospatial capabilities can be found in many different types of software.
While this is by no means a comprehensive list, this can give you an idea of the many different software resources available.
If you have questions or need help with research, please contact me at firstname.lastname@example.org.
To schedule a meeting, please email me and let me know your preference for day/time and for in-person or virtual.