calculation and analysis: How to use a previous numerical solution to numerically solve a differential equation?

When I solve this differential equation with NDSolve, I get a numerical solution for H[x]:

Code for the differential equation:

sol1 = NDSolve[{(H'[{(H'[{(H'[{(H'[x]) ^ 2 - ((1 + 6 H[x]^ 2) ^ 2 H[x]^ 2) / (
6 (1 + 18 H[x]^ 2)) + ((1 + 6 H[x]^ 2) ^ 2 E ^ -x) / (
18 (1 + 18 H[x]^ 2)) == 0, H[0] == 1}, H, {x, 0, 20}]

I want to use the numerical solution (the solution I get for the equation above) to numerically solve this equation (I want to obtain x

Code for the equation that I want to solve.

X & # 39;

Thank you!!