How do I set values in a form before it is displayed (opened)?

[kudzu]

TfmSendMailWEB is the class name, not the instance. You need to store the instance from Create.

Are you new to Delphi?

var
xPage: TfmSendMailWEB;
begin
xPage := TfmSendMailWEB.Create(Self);
xPage.edEmail.Text := 'mail@mail.ru';
xPage.Show;