QGIS frustrations

I haven‘t worke3d on the GIS portion of my work since 2021. In the interim, my old MacBook Pro was charged out for a new one that lacked Bootcamp of Parallels - programs that I needed to access te PC side of my machine, where I kept my GIS work. I neglected to have our computer folks back these up, so I am now trying to reconstruct them from Dropbox and G-drive saved files. What a mess. Complicating everything, QGIS has advanced, changed, whatever and I am struggling to learn the new terminology, etc. Grrr.