The vaccine just reduces the effect of Covid on you. You can still get, and transmit, Covid.
Vaccines, generally speaking, are reverse engineered viruses that force your body to produce an immune system response. Generally speaking, if your immune system responds to something once, you become immune to it.
There are many exceptions to the above. But the general rule > exceptions unless any of us are domain experts. Where'd you read the study out of curiosity? I'm very cautious of third or second party sources (a news article citing a magazine, citing a journal); there are many instances where the person writing writing an article for the general audience hasn't a clue lol. Those journals are hard to read!