Truly, truly

See how you translated this in John 1:51.

it is my Father who is giving you the true bread from heaven

The "true bread" is a metaphor for Jesus. AT: "The Father gives to you the Son as the true bread from heaven" (See: rc://en/ta/man/translate/figs-metaphor and rc://en/ta/man/translate/guidelines-sonofgodprinciples)

"gives spiritual life to the world"

Here the "world" is a metonym for all of the people in the world who trust in Jesus. (See: rc://en/ta/man/translate/figs-metonymy)