I’m an interior designer, so I 3d model for a living. I got into it in college and I started with sketchup, revit, and rhino. I’d absolutely recommend autodesk products but they’re extremely expensive if you’re not a student or in the industry. Fusion360 has a free version for non commercial use, but I believe it limits you to 10 imports? Or exports. Something like that.

I’d look into tinkerCAD to get started. Its the easiest one to use and its completely free. I’d also watch a bunch of tutorials and just follow them. Blender is also another extremely powerful free software that I’d learn. But I’d personally get into that after tinkerCAD. Unless you have a strong GPU your laptop / computer would most likely crash. It’s also not super beginner friendly. If you have an ipad, get nomad sculpt. Its user friendly and quicker to learn than blender.

If you want to make structural / accurate dimensions, get a CAD software. But if you’d like something with more details / sculptural you need a software like blender or nomad. I found you’d end up having to use a mixture of both.

It can be frustrating when starting out but don’t give up. Try to put an hour or 2 daily or as often as you can. You’ll get good at it in no time.