Entering the U.S.on the temporary visa waiver visitor program or on a temporary visitor B-1 or B-2 visa, you will have to have the intent to return to your home country after a short temporary visit to the U.S. If you are entering the US on a temporary visitors visa you cannot have the intent to stay in the US and adjust to permanent residency in the US. If the I-526 petition is approved while you are in the US you will have to leave the US and obtain your conditional permanent residency through US consulate processing.