As long as the TWAIN printer driver has installed correctly, you can scan a document into
any suitable image-processing software.
As an example, I'll use Irfanview. (If you've not already installed it, I strongly recommend that you do anyway. As an image-viewer, it's a zillion time better than what's built into Windows. It's also an excellent image processor):
https://www.irfanview.com/
Assuming that you're using Irfanview, first open the program (obviously!).
Go to File > Select Scan/TWAIN Source. If the scanner driver has been correctly installed, you should see it listed (and probably pre-selected) there. Click to select it. (Unless you install another scanner, you'll only have to do that once).
Next, go to File > Acquire/Batch Scanning.
Ignore the various options within the dialogue box that appears and click OK.
That will launch the TWAIN driver for your scanner. If it's the same as the one for my Canon device, you need to click on 'Preview' and then drag a box around the area to be scanned.
Click the Scan button to load the scan into Irfanview.
To save the scan as an image file, go to File > Save (or File > Save As), ensuring that .jpg is selected as the file type.
To save the scan as a PDF document, go to File > Print and change the printer from 'Canon Pixma TS3100 series' to 'Microsoft Print to PDF'.