Can I lose 65 lbs in 3 months?
Of course you can. There are a lot of questions. How old are you? What is your over all health? Are you at risk health wise?
The fastest weight loss plan for healthy people is a Ketogenic diet. Google it.
In short, it eliminates carbohydrates, and allows for high protein. Carbs are found in potatoes, breads, pasta and rice. Don't eat any of it. Eat lots of veggies and dairy. When eating dairy go for high fat. Whole milk, real butter etc.
Meats are allowed. Portion control is important.
Eliminate sugar. No sodas, fruit drinks or energy drinks. Coffee, tea and water are friendly. Do not add any sweeteners. Sugar, honey etc.
Read label and do not eat anything with carbohydrates. You can find plenty of list of carb content on the internet. Same with sugar.
Example is yogurt. Generally a healthy food. Plain yogurt is great. Checking labels of flavored yogurt, the ones that look healthy based on the label, and you'll see carb content in the teens or higher. That is for the small single serving.
A good carb day has the limit at around 40 grams for the day. Lower is better. If you waste half of that on one serving of yogurt, you won't last on a low carb high protein diet.
It is a serious diet that requires a serious mental state that is ready to make the sacrifice of not eating what you want.
Here is an article that may help. How I Lost 29 Pounds In 90 Days
At the end of the article it talks about a teenager with a pacemaker who lost 50 pounds in 90 days.