Which version of php have you installed on your server? Is it 7.0 or newer (best would be 7.2)? Elgg 3 requires php 7 and in case you still have php 5 on your server this might explain why the installation fails.

Same thing after changing the version to 7.2

So, does this mean you had used some php 5 version before? If this is the case, are you sure that the server definitely runs with php 7.2 now and not still on php 5.X?