Elements 14 will not open my raw files from sony rx10 m4

Your camera requires ACR 10.1.  I haven't tried it myself with Elements 14, but it may be possible to update your Camera Raw plug-in using the workaround found here.  I suggest you try downloading the plug-in for ACR 10.5.  If you decide to use this workaround, please report back if it works for you.

All new cameras require their own (totally new) raw format that no older converter can support.

https://community.adobe.com/t5/photoshop-elements/faq-will-photoshop-elements-work-with-my-camera-or-why-won-t-my-raw-files-open/td-p/4303022

So, you can either use the Sony converter bundled with your camera,

or buy the current PSE2021,

or the free solution to download the free Adobe DNGconverter, a standalone program that can batch convert a whole folder of your raw files to the universal DNG raw format that PSE14 can read and process. An additional batch operation but free and with the same quality/