Canada is on something like 120 volts 60Hz whereas the UK is nominally 230 volts 50Hz.
I have used US-sourced power tools in the past in the UK by using a site step down transformer, such as a Defender. These step down 230 volt power to 110 volt and the tools run OK on that despite the change in frequency. There are also step-up transformers which step 110 volt to 230 volts (which usxwhatvyou need), but the big downsides to these transformers is that they are heavy and they tend to cost in the £60 to £90 range. Because vacuums have quite powerful motors you'd need to look for a 1.5kVA step-up transformer in the UK (these are specifically a UK construction industry thing) and change the plugs to BS.4343 type. Personally, I wouldn't want tolug one of those around the house with me when vacuuming
American and Canadian homes often have a 220 volt supply as well - in the laundry room, basement or garage. AFAIK these require a different plug and they are only in one location in the house (for the washing machine and/or drier), but you cannot guarantee that you'll even have one.
If moving to the States or Canada you are probably better off replacing any electrical stuff unless it runs through a universal power supply (e.g some razors) or through a transformer which can be easily replaced (e.g. laptops)