Please do not feel ‘sorry’ for being a beginner, we have all been there, the objective here is to encourage using S3D efficiently while enjoying the experience.
Set out the Sketch so that each view is equidistant from the Axis Origin.
By Selecting ALL of the appropriate View it can be Rotated using Transform > Move/Rotate. Move the Pivot Point to the Axis Origin before rotating it 90º.
Prior to the following consider the modifications needed and incorporate them appropriately.
When taking the measurements of the STL Mesh commence with the overall dimensions and create two views.
Then Sketch only half of the Front View, the other half can be created using Transform > Mirror. The righthand vertical Line is used for Mirroring only.
Next Sketch the Side View, use Transform > Move/Rotate to place Lines at a precise Angle
Move the Pivot Point to the appropriate end of the Selected Line, drag the appropriate Arrow and Type in the required Value
Then Tools > Project the portion of the ‘comb’ needed to remove more of the Body with the upward movement. NB. Shown below as the full width of the ‘comb’ because it will be Projected from the completed Front View. This ‘comb’ View will also require positioning, probably further forward to achieve it’s objective: