You will probably need to copy the text from the email, then create a new mail and paste it into the body. Then you can edit out the email addresses you don't want included in the forwarded message.
If you don't know how to select the text, open the message you want to forward, long-press on a blank area of the message body, then move the green dots to the top and bottom of what you want to forward, then hit the double arrow icon to 'share' it.