Hi Helmut,
if you need to know the exact elevation of any point of the map you tap on, then the answer is No, I'm afraid: OsmAnd can only calculate the altitude from the Satellites' signal and the correction provided by the World altitude correction module, which is available in Download Maps menu.
Otherwise, you can obtain the approximate altitude from the Contour lines: just zoom in and you'll see the elevation markers on the contour lines themselves, at 10 m intervals.
Additional markers are available from the Map, i.e. for mountain peaks and other spots... provided someone has put a tag ele=* somewhere.
Kind regards,
Massimo