Scavenge - you can get any or everything you need
Day 1-10 (Kris): Since Kris is basically you in deltarune you can do what you normally do for the first 10 days.
Day 11-20 (Susie): Susie used to be mean so choose the most violent option, also when going to expeditions always bring the axe (cuz y'know susie has an axe in the game) also if the mushroom scenario pops up, eat the mushrooms.
Day 21-30 (Ralsei): he is the lonely (but very nice) prince so attend to their needs every time you can and when doing expeditions, always use ted or dolores (depending on who you choose.) if not, make sure the other family members wear a gas mask (cuz u wanna protect them) and, most of all, don't gamble or steal from the school or the old people.
Day 31-35 (Lancer): and the end of chapter 1 lancer takes over and becomes king while the actual king gets dethroned (his dad) So Timmy (which is now lancer) gets food and water every day while Ted (which is now King) gets to do everything, that mean expeditions, choosing who emptys the bucket, and going out to answer the phone, also, you can't give up the cards if you have them during this stage cuz lancers head is a spade.
Day 36-50 (Spamton): You Are In Need Of [KROMER] So Always Steal From [MEN, WOMEN, AND CHILDREN], Gamble, Get Supply Drops For Extra [KROMER], And Trade With Anyone That Comes Your Way. Never Give Up Any [ITEM], Do Not Let The Merrymen Enter, And Try And Take Care Of Either The Dog Or [KITTYKITTY].
Once all 50 days pass, you win the challenge, if you die or get rescued before 50 days pass, you fail,
And yes, i tried this challenge, its possible.