You can upgrade a 2017 MacBook Air all the way to macOS 12 (Monterey).
You may need to do this in stages – upgrading first to High Sierra, then to Monterey. (High Sierra introduced the APFS filesystem, and the High Sierra installer will automatically convert a SSD to APFS format. Later versions of macOS expect that SSDs are in APFS format, but might not have code to do the conversion.)
How to download and install macOS - Apple Support
Monterey is not one of the "most recent three" supported by vendors such as Microsoft and Adobe. However, even Catalina is enough to run current versions of the Firefox browser and the LibreOffice office suite. Monterey is enough to run current versions of most other major third-party browsers (Brave, Opera, Chrome, Microsoft Edge).
So if you upgrade macOS, install a current version of a third-party browser, and use that when accessing the sites for these streaming services, you'll probably have a much better chance of getting to watch TV shows and movies.