Need Details Regarding Exp certificate or experince submitting for Green card

[sreedevikarthika]

Hi ,
Do we need to file Green card with Same Exp what is filed in H1.Is there any relation between the H1Exp summary provided for H1 and the Exp details need to provide for Green card if filed through Employer.
Can I change any company or date when filed for green card which alredy is given when H1 filed.

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