is possible to upload data on the parent member?

For account and UD1, with the correct extensibility in place, yes.  With extensibility in account and U1 at a summary or parent level for the 5 year plan, you could achieve this.  But you have to leverage extensibility by scenario type (horizontal extensibility) to make this happen.

For entity, the only way to load to parent entities is using parent currency adjustments.  I would not recommend that for your use case, so for entities you have to load data to base entities and cannot load or input to parent entities.