I recommend downloading the free Tabata Timer app on your phone. You will be doing 8 rounds total with 20 seconds on and 10 seconds off. In the first video below I explain what a tabata is and some sample exercises for the core(gut). The second video is some more core options plus some bonus legs(glutes) exercises. Have fun! :)
Don't forget in order to be physically fit you must first be spiritually fit. My challenge to you is to find a scripture that speaks to you and meditate on it until you know it by heart.
Today's power verse: "Those who hope in the Lord will renew their strength. They will soar on wings like eagles; they will run and not grow weary. They will walk and not be faint."