How can I use this program on the ios phone?

Hello~~
I have developed a program here and packaged it into an APK file that can be used on the Android system. How can I use this program on the ios phone? Thank you

Unfortunately it is still not possible to compile the application into an IPA file (IOS application file), currently the beta testers only have access to Companion on iOS and we hope that Companion will be released publicly soon.

Thank you~~
So now it is not possible to directly convert from APK files to IPA files. Can they be converted directly after release? So can I only use beta testers to rewrite programs now?

In general, it is not possible to convert an APK file to IPA, but app inventor adds more programming layers to each component, designer, etc ... in swift code (which can be run by the variety of Apple devices) in addition to java code (which can be run on Android devices), so that device runs IOS will be able to run your application.
After releasing Companion on iOS you can run your app through Companion, the next step (which I highly expect) is that we can compile the app into an IPA file, install it on the device and also upload it to the App Store!

Can we know when exactly or an approximate time frame?

Unfortunately there is no timeline or publication date😔

Thank you~~
What can I do to participate in beta testers?

I think they have already reached the quota of the amount of testers, in the meantime wait until the public version is available