I quit added sugar for the new year. Went cold turkey. Sugar in fruits and such are fine, but nothing with sugar added. Traded one addiction for the next, and I'm up to probably 2 quarts of black coffee a day. Still better though.
It was easier than I thought and a few days in I took out calorie-dense food. Nothing against the potatoe, but if you don't do physical labor for a living, potatoes are no good. I had literal withdrawals. Two nights in a row I woke up nauseous, thinking I had a flu bug. Got up, drank some water and went back to bed.
Fast forward 5 months, with no additional exercise, I was down >10% of my body weight and blood tests (cholesterol, triglycerides, etc.) are down in the healthy range. I fell younger, and am more flexible and needed to buy hundreds of dollars of new clothes. I've also been able to add some junk food back in. Just some. Get on the scale every day and adjust as needed.
It. Is. Not. Easy. But it really is simple. There really are no excuses for being overweight.