Php pages not working on new host

Hello, I am building a site and its almost finished. All php pages displayed and worked properly on old host.
I then uploaded files to new host and I get error messages on a white screen. I have no idea what to do.
I am quite frustrated.
See the error here:

Any help would be greatly appreciated.

Are you sure that the file popup-contactform.php is in the same directory as index.php and the file name is spelt correctly?

2ndmouse Thankyou so much!
When I transferred the files over I didn’t put the files in the same directory. I am expanding my horizons into php so am a newbie but words cannot express my gratitude. I can’t believe it was so simple and I just couldn’t figure it out.
Thanks again !!!