Hello Elsa and welcome to the forum.
Have you managed to download and install a proper third party PDF reader on your Windows 10 machine.
https://acrobat.adobe.com/us/en/products/pdf-reader.html
OR
https://www.foxitsoftware.com/products/pdf-reader/
Afterwards, because Windows 10 defaults to "Edge" for PDFs you'll want to set your choice of reader as the default
Control Panel\All Control Panel Items\Default Programs -> "Set your default programs" (link)
Select your choice of reader from the left column and then, at the bottom choose "Set this program as default".
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