Warning: I'm not an expert on this or on anything. W. Sidney Allen's old Vox Latina https://www.cambridge.org/core/books/vox-latina/0D460CEF06E5B2210ABA29EDB6A

Warning: I'm not an expert on this or on anything. W. Sidney Allen's old Vox Latina https://www.cambridge.org/core/books/vox-latina/0D460CEF06E5B2210ABA29EDB6AB5F2A https://www.cambridge.org/core/books/vox-latina/0D460CEF06E5... is apparently still the standard starting reference for classical Latin pronunciation, at least for English-speakers. (Many nineteenth-century German philologists died to bring us this information, of course.) People such as Luke Ranieri on YouTube use a version of Allen's system, though a number of people including Ranieri claim that there should be five vowel qualities rather than the seven described by Allen https://www.youtube.com/watch?v=eH8E5RKq31I https://www.youtube.com/watch?v=eH8E5RKq31I . Note that if you want to speak Latin that's roughly faithful to how it was spoken up to (but not necessarily including) late antiquity, pronunciation is actually less important than quantity: basically, using clearly distinguishable short and long vowels in the right places (plus not running together double consonants in some places). I suppose it's similarly important to get the stress right, but at least that's generally agreed to be pretty easy. Classical Latin quantity feels weird and unnatural to English-speakers, and to Romance-language speakers, German-speakers ... : words often include one or two or three unstressed long vowels before getting to the stressed syllable, which might or might not itself have a long vowel. Even people who advocate for (classically-)correct quantity often don't consistently get it right. (And yes, Allen also did publish a Vox Graeca https://www.cambridge.org/ie/universitypress/subjects/classical-studies/classical-languages/vox-graeca-pronunciation-classical-greek-3rd-edition https://www.cambridge.org/ie/universitypress/subjects/classi... , too, but be careful: the pronunciation of Ancient Greek is a question that might actually get you into a fistfight https://www.youtube.com/watch?v=BybLbHPU7Qc&list=PLQQL5IeNgck0hFZ5oEfTV1Zhp_xksAgCz&index=9 https://www.youtube.com/watch?v=BybLbHPU7Qc&list=PLQQL5IeNgc... .)