Thank you for your reply; in fact I thought something similar so I tried
NDSolve[{D[x^2 y'[x], x] == x^2 Exp[-y[x]], y[0] == 1, y'[0] == 1}, y, {x, 1, 30}]
just to see if it worked but it didn't. I think the problem is related to the \frac{2}{x} but I can't manage to fix it adjusting...