When thinking about how much bandwidth you’re going to need, one consideration would be figuring out what will be going on at any one time…
For example, it’s 7pm - you’ve logged off from work, sat down for your dinner and then stick a 4K film on the TV (Netflix, Amazon Prime etc…). A 4K film will use between 15 and 25Mbps based on reports from both those providers. Meanwhile, the kids are on their iPads watching HD videos on YouTube - each full HD (1080p) stream will use around 4Mbps, 2.5Mbps for standard HD (720p).
Then consider that a device might also be running updates in the background - sadly it’s difficult to know how much bandwidth is used for updates, as this varies with what app and device it’s happening on.
However, if you were watching a 4K film, one of your kids was on Facebook (less that 1Mbps), one was on YouTube watching HD videos (4Mbps), and the other online gaming (up to 3Mbps) - it would be a much different picture -
Whilst still on the high end of the 37Mbps bandwidth, it leaves some room for additional traffic and fluctuations of existing traffic.
The above scenarios would be considered “peak time” in the house - but wait, there’s more! Peak time in your household will likely be peak time in neighbouring households, and contention on the local green-cabinet on the street can also mean a reduction in performance due to the high level of internet traffic.
37Mbps is a good speed, however it might mean you experience some “lag” with movies and games, and general internet use at peak times. During the day when there is less going on, i.e. the odd Teams/Zoom call, email traffic, kids remote learning via video - you may find 37Mbps is fine.
So it’s really down to time of day, and what’s going on at home.
I am assuming this is something like BT Infinity or some other FTTC service? If a full-fibre connection was available such as FTTP, I’d recommend going for something above 60Mb, to ensure a better experience.
I hope this helps.