My problem is that my laptop will select 2.4ghz if it is just doing normal stuff but if I want to do video calls I need 5ghz and it takes a while for the network to swap across to 5ghz (which it eventually does). That means that for the first 5 minutes of every call the reception is terrible because the 2.4 band isn't enough. I need to be able to move the the 5ghz band before making the video call. Given I work from home this is a big issue.
WiFi devices decide which access point and which band to connect to, and when to switch between them. Google/Nest WiFi does provide devices with some extra information (in the form of 802.11k and 802.11v) that can help them make better decisions, but not all devices support those specifications, and they are on their own. It sounds like your laptop is connecting to 2.4GHz because it gets a better connection in that band. It may be that it is just too far away to get a solid connection in either band (a good 2.4GHz connection should support video conferencing without difficulty). So, I guess my advice is to think about how to improve overall signal quality in your work area rather than trying to force the device onto one band or the other.
It looks like WiFi systems in general are moving towards a common SSID for both bands since it has advantages for transparently roaming between the two bands as you move closer and farther from even a single access point. Since devices make these decisions, the Google/Nest WiFi system can't really "force" a device onto one band or another. If your laptop is running Windows, you may be able to dig into the settings for its WiFi interface to do that yourself, though. I mostly run macOS and Linux systems here, but I have one Windows machine that is now on Ethernet. When I had it on WiFi, I seem to recall finding a setting for it like that.