I have had the same problem a few years ago, as I am an old engineer and I didn't use CAD software and I didn't familiar with those. So, I start with AUTO-CAD but after some days I found solidworks software which is very simpler. I suggest you go through it. It has a very good simulation and you can use it easily. If you have any questions or ambiguity you can find your answers on the internet or ask me in this forum.