sed replace a matching line with string code example

Example 1: replace text with sed

sed -i 's/old-text/new-text/g' input.txt

Example 2: sed replace from match

Just use a similar example with using ".*" regex with sed as following:
sed 's/match_pattern.*/replacement_of_match_and_rest_of_line/' file.txt

Example 3: sed replace line with no line

Use d option at the end of sed command string for deleting line of matches.
sed -i "" "s/matching_pattern/d" file.txt