GH (Growth Hormone) could be many things. HGH (Human Growth Hormone) can only be one thing or the FDA would sanction (penalize) the company selling it.
Many supplement manufacturers / scammers make a minor change to to the name of a recognized substance that an uneducated, naive consumer will still think is the real thing.
Human Growth Hormone is injected subquetaneously (just under the skin into stored bodyfat) using a small syringe (29 guage) commonly used for injecting insulin.
The HGH molecule is too large to pass through the skin and cannot be administered transdermally... I am not aware of any oral form.
There are countless, worthless products which only result in separating the scammed purchaser from his cash.
Real HGH is expensive ($4 to $10) an iu and can only be purchased legally with a prescription.