It looks like you are trying the original Wix tutorial method they released in 2017.
If you follow Wix’s tutorial you will be able to accomplish what you need. You may need to modify the insert just a tiny bit as you want to save more data than shown in their example.
I must warn you though, should you attempt to use Wix’s tutorial method ---- there is a small chance that a ‘verify your email’ message may automatically be triggered by Wix even if you dont code it. It may or may not show up radomly, but when it does ---- it will break your registration process therefore your ‘insert’ code may never be triggered. (I provided this feedback to Wix a few months ago. Not sure what their plans are for this. Because of it ---- it is difficult to create a custom registration process without added limitations for fear that the registration flow will break.)
You might also want to consider using the Members Area pages as it involves less code. (You can find several tutorials on YouTube for this.)