How can I get fit again?

The only time that I actually ever got fit and was serious about it in my life was during the summer of my senior year of high school. One of my teachers passed out candy and a girl in my class said no thanks & the teacher asked why and she said that she didn't really eat candy. All of us were so shocked because we're greedy, hormonal, growing teenagers. Then she explained that she only really ate fruits & vegetables because she was a pageant girl and had to keep her physique. My teacher was very impressed with her. Long story short, I found her IG & was so impressed as well & thought wow, I want people to be impressed with me & I wanna look great like her (she also won most beautiful of our class that year) anyways, there was another girl on IG who was the same age as I during the time & her body was amazeballs and I was like yeaaaaa, I've gotta do SOMETHING. At this time in my life, I really didn't like my body & wanted to change it. I did it all for the wrong reasons but it worked. I still lived with my parents then, my diet only consisted of clam chowder and applesauce because that's literally all that I enjoyed, not because I was trying to eat less or anything, I worked out 5-6 times a week and I didn't even realize that I was getting more fit or anything because I just knew that I didn't like my body and working out obviously must be the trick. This was way before I knew anything about good & bad carbs, protein, building fat on top of muscles, carbs, green leafy vegetables, red meats, oh and did I mention CARBS? lol ignorance truly was bliss. I was so nonchalant to my diet until my mom asked me if I was starving myself. And in my mind I'm like no, I'm just working out. But I really hadn't even noticed changes. And I STILL wasn't at my desired goal (wanted to be more ripped) Here are some before and after pics

Now looking back, if I'm being honest my body did look great and I was the most active and consistent than I have ever been in my life, and although I was doing it for me, I did it for the wrong reasons I believe. Nowadays I'm on these on and off binges of "being healthy & getting fit" but let's be realistic. I'm 22 now, real life is kicking in, I have 2 jobs and this is my senior year in college. As much as I want get fit again and be consistent, I'm realizing that I'm having a very hard time. For one, I know too much. Knowing all the rules about food (basically how at the end of the day, everything is pretty much bad for you) is stressful as f'! Because I know what's good but my temptations always make me wanna go to the bad, ESPECIALLY after long stressful days and I just wanna come home and sleep. It was easier back then. And then I had more time back then and now I have to make time that I don't have. It's just a continuous cycle of "Yea, I'm gonna get back in the gym" to "I have 2 papers due by midnight, I have to get up at 6 in the morning for work, so I'll just workout some time tomorrow and I'll pick up dinner otw home". See, but now I'm content with my appearance but upset with my health. Now that I'm older it's the complete opposite but either way, they both require dedication and I WANT to be dedicated but I just seem to not be able to actually BE dedicate. Something's gotta give y'all cause I look like the pictures on the right again and I'd be comfortable with that IF I didn't know that that body is filled with late night pizza runs, Utz chips, Doritos, and cookies from PMS cravings 😭