https://www.amazon.com/Wireshark-Network-Analysis-Second-Certified/dp/1893939944/ref=mp_s_a_1_7?crid=1U1LOJFPX879T&keywords=wireshark&qid=1668824060&sprefix=wireshark%2Caps%2C308&sr=8-7 and there’s a practice test book that goes with it that should be easy enough to find, the questions on the exam are very similar to many of the ones in this practice book
i came here to say this book has helped me a ton with wireshark: https://www.amazon.com/gp/product/1893939944/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1
but that website looks pretty damn good.
this: http://www.ine.com/self-paced/technologies/wireshark/wireshark-bundle.htm coupled with: https://www.amazon.com/Wireshark-Network-Analysis-Second-Certified/dp/1893939944/ref=sr_1_1?s=books&ie=UTF8&qid=1472473761&sr=1-1&keywords=wireshark+network+analysis should help you greatly.