Worth seeing what the Ofcom coverage checker gives you.
The maps supplied by the networks are computer predictions and can be unreliable.
My phone is dual SIM running 3 and EE. Both are supposed to have very good indoor and outdoor signal where my daughter lives, truth is both struggle with signal at all, both indoor and outdoor. Thankfully, my 3 SIM has Wifi Calling
EE and Virgin may have slightly different signal as Virgin do not have access to EE's 800Mhz 4G
Only thing you can do is move to another provider which doesnt use EE
Not true. Others have pointed out the obvious WRT WiFi calling & 800Mhz. The EE website coverage map has a long-standing bug (I think) where it can reports the 4G800-inclusive coverage regardless of which phone you tell it you're using. The Virgin website map correctly reports the non-800 service and "should" be reasonably accurate.
The Ofcom map (https://checker.ofcom.org.uk/mobile-coverage) is, in my experience, fairly accurate but again includes 4G800 for the EE-predictions. There's ultimately no substitute for trying networks-out in a particular area before committing.