People should share the original files or at least step files along with the stl files. But if you must work with stl, Fusion works brilliantly for this. You can open the stl file, which gives you the usual mesh that's hard to work with. You then convert that mesh to a solid object, on which you can use "direct modeling". It's not the same as a parametric object, but the editing features are quite powerful and sort of mindblowing. [1]

If you have the paid version of Fusion, you can run "feature detection" to turn things like holes, fillets, extrusions etc. into dedicated features which are even easier to edit. [2]

[1] https://www.autodesk.com/learn/ondemand/curated/direct-model...

[2] https://www.autodesk.com/learn/ondemand/curated/direct-model...