ESA freely distributes all data acquired by the Sentinel program from here: https://scihub.copernicus.eu/ https://scihub.copernicus.eu/ There are also multiple

ESA freely distributes all data acquired by the Sentinel program from here: https://scihub.copernicus.eu/ https://scihub.copernicus.eu/ There are also multiple partner sites with the data, including cloud providers that can you a VM with the data files already mounted. Software is a bit harder, for simple interferograms of two measurements you can just use open source Sentinel-1 toolbox ( https://github.com/senbox-org/s1tbx https://github.com/senbox-org/s1tbx ) to align, diff, subtract geometric corrections based on an elevation model and convert the measurements to geographic coordinates. This will be enough for seeing large scale motion, like earthquakes. For better quality processing you need multi-temporal InSAR which can estimate atmospheric phase delay, height of persistent reflectors which will cause a geometric phase difference due to slight differences in measurement location (measurement baseline). There is some open source software available for this (e.g. StaMPS), but I can't vouch for its capabilities.