Both versions are correct, but they convey slightly different nuances in terms of punctuation usage and capitalization.
The first version uses a comma after "here," which indicates that the dialogue tag ("he said") is part of the same sentence as the preceding dialogue. The first letter of "life" is lowercase because it continues the same sentence as the preceding dialogue. This version feels like one continuous thought with the dialogue and the tag connected.
The second version capitalizes "He said" as it treats it as a separate sentence from the preceding dialogue. This creates a slight pause between the dialogue and the tag, giving it a different rhythm. Additionally, "Life" is capitalized because it starts a new sentence.
Both versions are grammatically correct, but the choice between them depends on the style and flow you prefer.