IMHO these online 3d modelling programs will be much more taxing for your system than standalone applications with the same feature set.
I remember running Blender on some Friends crusty ~15yo Thinkpad, if you can get over the initial hurdle of getting into the control scheme you’re golden.
If it doesn’t run try some older Version. (but don’t go below 2.5 or 2.6 or what was it where they made the GUI better?)
Wait, you want to go easy peasy? 8)
Try kHED, it’s the definition of easy, it doesn’t have many features and you get by without shortcuts at first.
You may need to install the runtime library from microsoft, that they mention on the download page though.
But seriously, try to get into Blender, it actually allows you to create game related content that doesn’t look like shit.
Oh and wait till you work with textures, that will surely be a fun experience with online modelling tools : Smooth, fast and definitely not frustating workflow guaranteed!
You problem is that many of these older Intel graphics processors do not support OpenGL properly.
If you find a program written with DirectX it’ll probably run.