But then a friend who is a doctor told me the pfizer shot had better efficacy, so now I trust no one.
I would question your friend. After the second dose the Pfizer/BioNTech vaccine has an efficacy of 88%. The Moderna vaccine has an efficacy of 93% after second dose. Those numbers are very well known across the global scientific and medical communities who know these vaccines.
That does not mean Moderna is better than Pfizer. Both are highly effective at keeping folks out of hospital and keeping severe illness at bay. Both vaccines are highly efficacious.
Efficacy is the degree to which a vaccine prevents disease. Effectiveness refers to how well it performs in the real world.
Moderna's shot contains 100 micrograms of vaccine, more than three times the 30 micrograms in the Pfizer shot. That is not to say Moderna is better than the Pfizer as both are initially better than 88% (Moderna 93% / Pfizer 88%).
The effectiveness of the Pfizer/BioNTech vaccine at preventing infection by the coronavirus dropped to 47% from 88% six months after the second shot. Yet, you are still well protected from hospitalization and severe illness at 47%. All current global scientific data very clearly demonstrates this.
Moderna claims that after six months their efficacy is still at 93%. We will know for certain when their presentation comes on Oct 14th.