Don't let the perfect be the enemy of the good. If you can just start by reducing the added sugars, you can monitor any changes as you go along. If it seems helpful, you can then take more expensive/drastic measures.
If you don't want to do food prep, or you don't care for traditional high fat, moderate protein, low carb food options, you can get meal replacement shakes.
I prefer KetoChow, rotate through several different flavors, and it costs me ~$3/meal. It take 5-10 minutes of prep every 2-3 days (fill blender bottles with heavy whipping cream, ketochow powder, water, shake, toss in fridge). At 5' 6", I went from ~180 lbs to ~155 lbs. I don't need to work out, I maintain a healthy weight, and it's both affordable and non-time intensive.
Otherwise, cut breads, sugars, and liquid calories (regular soda & beer) out of your diet. I know people who eat primarily meats, cheeses, and green veggies, and they feel better than they ever have and quickly shed any excess fat without exercise.
It’s doable, but for social reasons, not easy.
Having the occasional sugary dish isn't going to ruin you. Anything you do to reduce sugar is better than doing nothing.
This would represent a radical and complete change in diet in me and probably many other people. Since it would mean having to change from most cheap preprepared versions of common foods such as pasta sauce, like you mentioned, and even regular store-bought bread. These foods would either more considerably more expensive or time-intensive versions that don't include sugar, or replacing them with completely unlike foods.
It's in no way an "easy" change, and involves so much alteration that I doubt the significance of the "no sugar" component matters as much as the other collateral changes.