The device originally supported Android by default, so www.acer.com, log a support ticket with Acer. But it is also 5 years old so the very last update would have been sometime in 2023.
You could bang your head against a lot of brick walls and compile your own android OS developer.android.com and applications. Installing it on the device would prove to be the most difficult part of the entire process (trusted boot - Google/Acer decides what OS can run on “your” hardware). And because you compiled your own OS you have the ability to remove or disable the default google spyware, so your device would not be granted access to the “google play store” for applications. You could probably point it to F-Droid for some open source applications. If you are a embedded systems software developer, LineageOS might be a better choice (It will not work by default for most hardware).
Another problem with installing your own custom Android OS would be all the binary blobs for your hardware not existing for a newer Android kernel, so you might loose the ability to use some hardware inside your device (e.g. WiFi, Bluetooth, speakers, microphone, touchscreen, MEMS accelerometers, camera, USB, battery, lcd, …).
You need to find somewhere on the internet where there is a high concentration of knowledge about your particular hardware and the Android OS or one of it’s forks. Here is opposite of where you need to look (On a site about RISC-V you are unlikely to find optimal support for ARM based hardware).
P.S. Kidnapping a preexisting thread that has nothing to do with your problem is seen as bad (it is basic netiquette to make a new thread for an unrelated subject). Re-purposing a thread that has not been posted to in ten months is something that a spam bot would do, it makes information harder to find. If you read the subject “Expermental debian sid image”, would you assume that was anything to help you with your problem.