Depends on how deep you want to go. As a start to get a "feel" i would suggest a practical exercise in Resolve:

Setup 3 nodes, node 1 use the ResolveFX colour space transform plugin to convert to linear from your source, then node 3 convert back to the source space from linear (just change gamma for now and leave colour). In node 2 go to the RGB mixer and uncheck preserve luminance.

The RGB mixer is a 3x3 matrix. You don't have a ton of precision here and the panels offer slightly more but it will give you an idea.

Play around with adding different amounts of each component to each channel. As a tip, make sure each channel sums to 1.0 to avoid overall tint shifts. For instance, say for the Red channel you increase red's contribution to 1.25, leave green at 0.0 and set blue to -0.25 (or RR=1.25, RG = 0.0, RB = -0.25) these 3 values sum to 1.0 so the overall gain of the red channel remains the same and doesn't introduce a tint, but the mixing of the colours has been affected.

What you're doing here is applying a 3x3 matrix in linear. So you take the input RGB and do matrix multiplication (RGB = 1x3 vector multiplied by a 3x3 matrix). So looking at the ACES dctl we have the following matrix:

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`0.9404372683, -0.0183068787, 0.0778696104`

0.0083786969, 0.8286599939, 0.1629613092

0.0005471261, -0.0008833746, 1.0003362486

Notice here each row/line sums to 1.0 also (last line probably suffers some rounding/precision error but close enough). The first row/line is the red channel (RR, RG, RB), the second the green channel (GR, GG, GB), etc.

In the DCTL it shows you the math too:

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`result.x = mat[0] * p_R + mat[1] * p_G + mat[2] * p_B;`

result.y = mat[3] * p_R + mat[4] * p_G + mat[5] * p_B;

result.z = mat[6] * p_R + mat[7] * p_G + mat[8] * p_B;

p_R, p_G, p_B is the input pixel separated into each channel (RGB). Result.xyz is the output pixel also just storing RGB (calling it xyz here).

So replacing the variable names to make it clearer and inserting the actual matrix, look at it as:

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`outRed = (0.9404372683 * inRed) + (-0.0183068787 * inGreen) + (0.0778696104 * inBlue);`

outGreen = (0.0083786969 * inRed) + ( 0.8286599939 * inGreen) + (0.1629613092 * inBlue);

outBlue = (0.0005471261 * inRed) + (-0.0008833746 * inGreen) + (1.0003362486 * inBlue);

That's all the DCTL is doing. The output is a single pixel made from RGB again. It assumes its in linear as there's no gamma transform. So if you used the Resolve CST plugin to transform from the working space into linear, and back, you can apply this in a node in-between using the example setup i describe above (just use the DCTL in node 2) and should be okay.

We're already greatly off thread topic so hopefully that helps (with some google to fill the gaps or take you further).