Most fit individuals with some mountain walking experience can make it to the top of Africa. You do not need to be super fit – just take it slow (‘ pole-pole ‘ the guide will say) and be determined.
Nisimulie Africa is among the highly commended Kilimanjaro trek operators with an excellent reputation and a very high success rate. But the success mainly depends on you – it is up to you to make some important choices, in particular the route you opt to ascend and for how many days.