Hi @dovilemackeviciute857,
I started from scratch on this. I made a video of my process.
You will see first that using -DWGUNITS, I verify that my drawing units are in inches as it appears you are from the US. Then I use Units to verify that I am in Architectural units and that I have set my Angle Precision to be pretty high. I did this as I noted that many of your walls are not actually perpendicular but off a very slight amount. I am unsure what units you are working in as many of the rooms did not look to be a realistic size. I believe that you have another thread about furniture models and how to get the scale right for insertion into your model. It is imperative that you work with real world dimensions and draw at 1:1. Then, if the furniture is drawn in MM's you can apply a scale factor.
Once I have the 2D walls in place, I then use Presspull to bring them up to a specified height. I show in my video how you can make the Presspull easier by only working one one part of the 2D plan at a time. I also show that once you have a height of a solid that it can be adjusted later. Lastly, I show how you can use UNION to join solids.

Please select the Accept as Solution button if my post solves your issue or answers your question.
John Vellek
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