Drag Mismatch with OpenFOAM

I am trying to calculate the drag on the wing using OpenFOAM. I used the OF forces function and got some drag values. I tried the procedure shown in this https://www.youtube.com/watch?v=J944HOj_4b0&t=291s video to find the drag and lift using paraview but the drag values have a considerable mismatch. After searching around this forum and in google I came to know that paraview does not calculate the viscous drag which has to be calculated using the wall shear stress. I don’t know how to calculate this wall shear stress in the latest release of paraview