I am switching from a Windows PC to a Macbook Air and my Hauwei e352 USB dongle works on my PC but won't install properly on the Mac and connect to the internet.
Your Huawei e352 3G modem dongle is going to need a driver before it will work with your Mac. You didn't mention which MacBook Air or what version of macOS it's running, however, this site has drivers for your Huawei. The problem is that the drivers are for an older version of macOS and may not work with newer versions of macOS. You will likely need to do some googling to find newer drivers.
Most USB Hi-Speed 3G or 4G LTE dongle modems are built for Windows and normally are more difficult to get working with macOS. Don't know where you're posting from, but free WiFi is almost everywhere and nowadays almost everyone has an iPhone or Android phone so the need for those kind of modems is just not as demanding as it once was. When I'm out and about, I can use my iPhone as a hot spot. I have no need for a dongle.
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