two people speaking one camera

two people speaking one camera - is there any way to record sound from two sources at once onto one trek in production

say you are getting an interview from
person A
and
person B

onto say DSLR (or GoPro or iPhone or Android)

there is no way a Y cable would work? as some people suggested to me …

usually Y cable is a splitter of audio NOT a combiner of microphone input right?
are we sure?

I guess I need this…

two people speaking one camera