Here the word "they" is used to refer to Jesus and his disciples.
# he gave thanks for them
"Jesus gave thanks for the fish"
# They ate
"The people ate"
# they picked up
"the disciples picked up"
# the remaining broken pieces, seven large baskets
This refers to the broken pieces of fish and bread that were left over after the people ate. AT: "the remaining broken pieces of bread and fish, which filled seven large baskets" (See: [[rc://en/ta/man/translate/figs-explicit]])
# Then he sent them away
It may be helpful to clarify when he sent them away. AT: "After they ate, Jesus sent them away" (See: [[rc://en/ta/man/translate/figs-explicit]])
# they went into the region of Dalmanutha
It may be helpful to clarify how they got to Dalmanutha. AT: "they sailed around the Sea of Galilee to the region of Dalmanutha" (See: [[rc://en/ta/man/translate/figs-explicit]])