Here "I" refers to Moses. The phrase "at that time" refers to when the Israelites were at Horeb, which is the same as Mount Sinai. AT: "When we were at Horeb, I spoke to you" (See: [[rc://en/ta/man/translate/figs-explicit]])
Here "to carry you" means "to lead you" or "to govern you." AT: "It is too much for me to lead you by myself" (See: [[rc://en/ta/man/translate/figs-idiom]])
This is an exaggeration that means God has greatly increased the number of Israelites. AT: "a great crowd of many people" (See: [[rc://en/ta/man/translate/figs-hyperbole]] and [[rc://en/ta/man/translate/figs-simile]])
# a thousand times
The phrase "a thousand" is a metaphor for "very many." AT: "very many times" (See: [[rc://en/ta/man/translate/figs-metaphor]])