Hey there, MariamAlishaba!
Thanks for reaching out in Apple Support Communities! We understand you received a pop-up in Safari on your iPod. We can definitely understand your concerns and would be happy to lend a hand.
It sounds like the pop-up you received was a phishing attempt. We recommend using the following support article to further assist with preventing pop-ups and learn about phishing:
About pop-up ads and windows in Safari - Apple Support
Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support
All the best.