Eat healthy foods

Exclude unhealthy foods.
Exclude meat, dairy products, eggs, bleached flour, salty, fatty, refined, sugary, and artificial foods such as preservatives and additives as they are linked to many diseases.

Change the recipes by replacing unhealthy ingredients with healthier ones.
Make a list of meals you eat often and then exclude/replace the unhealthy ingredients you usually use. For example, remove butter, replace cow's milk with plant-based milk, replace meat with mushrooms and legumes, replace an omelet with a smoothie for breakfast, replace egg in recipes with flaxseed egg, etc.

Include more healthy food in your diet.
It’s best to include vegetables, fruits, tree nuts, legumes, and whole grains in their most natural form as possible.  Raw or lightly cooked fruits and vegetables, soups, smoothies, fresh salads, fresh nuts, cooked grains, and so forth are examples.