If your native language is English, Mandarin pronunciation is definitely achievable. Most of the sounds can actually be approximated using English, with only a few initial consonants being slightly different—but there aren’t many of them. For most learners, the real challenge tends to be the tones, since they’re very different from anything in English.
However, once you understand the basic rules and consistently imitate native speakers—by repeating after them and practicing with simple characters and words, then moving on to phrases and sentences—you’ll notice steady improvement.
I’ve found that my students usually pronounce individual characters quite accurately. It’s only when those characters are put into words or full sentences that the tones might not sound quite native. This shows that Mandarin pronunciation is absolutely conquerable. That said, sounding truly native does take time and consistent practice.
But don’t worry too much—Chinese people are usually just thrilled to hear you speak Mandarin at all! No one is going to criticize your pronunciation, so be brave and start practicing with confidence!