How can we maintain some features like holes and cuts same as the original and in its scale model: if we scale to 1:2 ratio

That is not possible. You'll need to re-create the proper holes and cuts "after" the scale feature. 'Delete Face' might be a good command for eliminating the holes and cuts that get scaled up.

Without seeing your specific example, my guess at the workflow would be this:
1. Scale the model
2. place sketch points, or use 'offset surface' with a dimension of 0, or come up with some other convenient way to locate the holes and cuts prior to performing step 3
3. 'delete face' on all the holes, cuts, unwanted geometry of incorrect size
4. use the references created in step 2 to re-create the holes and cuts with the proper size, assuming they want to be in the same location as the original features.

This also assumes there's a reasonable amount of holes and cuts to re-create. In cases like this one should always weigh the options to determine whether or not it's worth the extra work, or if a different approach that doesn't require scaling the model such as re-creating it at the new size, would be more time-efficient.

There also might be better options, but without seeing your specific geometry, and knowing the intent of your design and how you intend it's re-use, it's hard to say.

A much simpler solution:
Make the cuts after scaling the model.