How to model complex landscape

I am having trouble to model a sloped landscape from a 2D cad. The landscape is a ramp consist of multiple levels and connects to a landing which has an uneven level as well. Any way to build this accurately?

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Plan

Welcome. I’m guessing you did not intend to post this three times, but the good news is you have successfully asked your first question.

Yes, there is a way to model this accurately. I see you are using SketchUp Free, so you are just working on this as a hobby and will not have access to extensions. We will need to look at a way to use the native tools available to you, which is possible. What kind of data do you have to start with? Does your 2D cad include elevation data? I see in the image some contours (but not on your ramp) and some numbers but it’s not clear what they are. You would need to attach the CAD file you have or your .skp file to a response here so we can see what you are working with, then we can give you use-full advice.