1) It's not "r" but "ř."
2) It doesn't sound like j or zh.
3) Check the introductory tips and notes on pronunciation.
4) There's also Forvo, YouTube, Reddit or plain ol' Google to help you along.
Well, how can a say this? Hmm the "ř" in Czech should be pronunced as two "r" (rr) As in spanish/latin pronunciation. It sounds like a bee buzzing
Do not confuse a rolled r - an alveolar trill with ř which a is raised alveolar fricative trill.
Check the examples and the recordings in https://en.wikipedia.org/wiki/Raised_alveolar_non-sonorant_trill It also includes the Spanish rr.
I translated it as "big animal" and it was marked as wrong - is there any difference between big and large?