SHELL

sed replace with newline

For substituting with newline use sed command to replace a match with a
not used char and tr command to replace that char with a newline '
'
#For example:
echo "123." | sed -E 's/([[:digit:]]*)./1|next line/' | tr '|' '
'

sed replace all until match in line

echo remove_staystay... | sed 's/.*(stay.*)/1/g'
stay	#remove all but from last ocurrence match until end

sed replace from match to end of line

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