Don't know how to make a fan blade from 3D sketch

I want to make a fan NMB model 2004KL-04W-B50, which I will use in SolidWorks flow simulation to optimize the device I build.

I have a stl format files from 3D scanner of the blades of the fan. I imported one fan blade (a dxf file) into SolidWorks and made a 3D sketch of it. I then correct the sketch a little by using more accurate dimensions (the scan is not so good quality).

Now I do not know how to extrude my sketch (blade.SLDRT) or better make another 3D sketch and use Lofted Boss/Base. Then I hope I will be able to make a fan.

I hope you can help me. Thank you in advance.

Edit:

I made another 3D sketch so I could use loft, but it doesn't work. the error is: Cannot knit sheets together. I tried using surface loft and it works:

How can I change it to a blade? I will then have to adjust the edges ...