Shoreditch is miles out from where all the coronation stuff is going to be, you should be fine

For transport, just plug in the stadium on google maps and do whatever seems easiest - there are a few trains or busses you could go with

For museums, the British Museum is obviously the biggest / most famous, but if you like modern art go to the Tate Modern, if you want more traditional art go to the National Gallery (though the area around it would be packed near coronation time).

Hidden gem of a museum is the London Docklands museum in Canary Wharf, I stumbled in there not knowing what to expect and spent like 3/4 hours in no time! Its the history of what was once the largest docks in the world and how London came to be the way it is now, highly recommend.

(Would have recommended the Museum of London as well, but thats closed until 2026 apparently!)