A basic example of how you can use the prfpy package (https://github.com/VU-Cog-Sci/prfpy/tree/main/prfpy) to fit fMRI data.
Example time series, and the design matrix are included.
If you have already done prf fitting and would like to plot data on the cortical surface, I would reccommend using pycortex (https://github.com/gallantlab/pycortex), I also have a package which can help with basic surface plotting, using tools like blender and freeview (https://github.com/mdaghlian/dag_prf_utils).
Some other useful repositories / links for the prf inclined: