That I would not attempt.
They are misleading.
It isn't a nokia n800 they are talking about here.
More like mistakenly referring to the nokia n8-00 or nokia n8 in word only.
The methods of putting android or rather nitdroid (in particular for the actual n800) are not as simple nor as easy as is suggested.
The performance and functions which do not work consequently do not make it something I would flash over diablo turbo for.
There are chances that it will fail and potentially brick your device.
As well it is not lollipop...much older version of android / nitdroid which is compatible as well ...for the nokia n800.
I would avoid trying this at all costs.
The photos aren't even of a n800...not a NIT anyway.
Ordinarily I wouldn't suggest android / nitdroid on the n800...
except for research purposes by an individual knowing exactly what they are doing.
There are faaaar more os's easier, more interesting and that have more functionality to try with the n8x0's.
In point of fact ...my best suggestion in this regard is Easy Debian...
Even though it is old ...it still works admirably.
There is a huge long list of os's which individuals have gotten to run on the n8x0....to one degree or another of functionality.
I'll post a list of them all...the ones I know of and have researched...which is I believe all of them...here on this thread tonight.
It is a pretty long list I think you will be happy with.
But yeah ...normally I'd suggest avoiding installing android / nitdroid at the best of times for new people...
But this page isn't even meant for the n800 NIT proper.
Do not attempt.