I am using Angular 4 with system.js and I do not have angular-cli.json

I am upgrading it to Angular 8. I did changes using below link:

[Issue after upgrading Angular 4 to angular 8](https://stackoverflow.com/questions/59052007/issue-after-upgrading-angular-4-to-angular-8)

I have also read Angular.io but not working for me. 
So I upgared it to Angular 5. I did not get issue in console but when I run application Ui is not displaying.

Do I need to convert system.js to CLI first before upgrading?