If you carry out something and go, the result is still enforcement, carrying out, or implementation of whatever it is. There’s no point hanging around after you’ve enforced something! So you always carry out and go.

This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.

You might sometimes see せこう as an alternative reading, but しこう is the more common version.