Ask for a question about how to using AlphaFold Protein Structure Database to calculate the RSA?

Hi,
Thanks for your great work! I‘m new to AlphaFold Protein Structure Database. Recently, I have performed a lysine labeling experiment and need to calculate the RSA (relative solvent accessibility) of lysine residues in human like the figure described below. There are only a few sentences which describe the RSA calculation. I have searched the database (https://alphafold.ebi.ac.uk/) but find no way to calculate RSA. It must be that I don't know how to use this database. Since I'm new here, I have no idea about how to perform this analysis. Here I sincerely ask for your help. Thanks a lot!