How do i find a background curve to a graph, i have data fitted with a spline and i need to find the background curve

I have been trying to understand the example examples/Optimization LSSolve section (at the bottom) and use it for different data and a different equation, i only want to find residues for omega_o, F, m and b not omega in the equation F/sqrt(m^2*(omega^2-omega_0^2)^2+b^2*omega^2) How do i just find residuals for these four unknowns only. Thanks

I have the fuction F/sqrt(m^2*(omega^2-omega_0^2)^2+b^2*omega^2 and i need to fit data to it using the LSSolve command, i have no idea how to do this any help would be much appriciated. thanks.

How do i show data points on spline on same graph and integrate to find the area under curve. i have the spline and the data but cannot get them on the same graph

How do i use LSSolve to fit the correct resonance function to a set of experimental data, thanks