ltspice - Obtaining Bode plots by using Laplace transform and time domain data from SPICE

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In LTspice in time domain, I apply a step function V(in) and obtain V(out) plots as below(I skip initial op. point solution):

I know that in AC analysis one can plot the transfer function for the gain and the phase much easier.

But my question is different. I want to export the points for V(in) and V(out). And then I want to obtain the transfer function myself with these data.

Since X(s)*H(s)=Y(s) where H(s) being the transfer function, X(s) is the Laplace transform of input and Y(s) is the Laplace transform of output. So I plan to do the following:

L{V(in)}*H(s) = L{V(out)}

And then I plan to find H(s) by using MATLAB or any other tool. One of the reason trying to do is to check if my results for H(s) will be similar to the one in LTspice. I also plan to use this method for a real life situation.

My question is:

If my way of doing is makes sense, to obtain the Laplace transforms of V(in) and V(out) which interval should I use? As you see the plots start from 0sec to 1sec. And the step ipout starts at 0.1sec. Can I just take the Laplace transform's of Vin and Vout for the entire 1 seconds and do the math? Is there any restriction here?