I can't help with specific software however -
Google - free cad software
https://all3dp.com/1/best-free-cad-s...ograms-design/ Seems a nice article
Use one that uses a "standard" or at least widely used file type.
.dxf as I recall is a published Autocad format intended to transfer drawings between applications
.dwg as I recall is Autocad's internal format but it has been reverse engineered and many packages support it.
Good luck.