Well, you could do it the easy way with events..just have each skill a variable.
Events could be set like;
Conditional Branch(CB): If 1 "Axe" is owned
>true
CB: if Variable[01] < 10
"Sorry, you cannot cut this tree yet (skill too low)"
if Variable[01] > 10
[Action of cutting tree, obtained Logs]
>false
"You need an AXE to cut this tree"
end
Something like that