General Information:

Moses speaks to the Israelites as if they were one man, so the words "you" and "your" here are singular. (See: rc://en/ta/man/jit/figs-you)

with all your heart and with all your soul

Here "heart" and "soul" are metonyms for a person's inner being. These two phrases are used together to mean "completely" or "earnestly." See how you translated this in Deuteronomy 4:29. (See: rc://en/ta/man/jit/figs-metonymy and rc://en/ta/man/jit/figs-doublet)