how to convert xray tiff files to ct scans using fdk algorithm

what code can I use to convert xrays into ct scans?

I have a bunch of tiff files that I want to reconstruct into a 3D CT scan which I can then save as a surface file or mesh.

I found that I could possibly use the FDK algorithm to do so.

I have no programming background so if the code could also be explained that would be great.

Thank you

Anthony