Glad you edited the OP, it made not a bit of sense.
And to answer your request (now edited out) I have no need to look up what things like an '3 x AA Battery' box is, I have some 45 years experience in electronics.
Set the multimeter to the range that is the one above 26V, although 26V is not a common quoted eBike battery voltage, they tend to be quoted as 24V, 36V, 48V etc.
It probably makes not much differrence anyway, of the many many multimeters I have seen over the years most all were protected against voltage overload, although more care is needed with the moving coil type multimeter (non digital type).