This question is very common online. The difference it two basic things. Vegans like and use oil and processed food vs Whole Food, Plant-Based avoid oil as much as possible and use ingredients that you can read. Such as Tomatoes, Potatoes, Beans, etc. Here is a great chart:
Getting rid of processed foods and oils is difficult at first, but you can get there. Basically I can cook without oil after a slight learning curve but at first it can be difficult because most Vegan dishes use a lot of EVOO. You can see a great chart of what to eat and what not to eat on T. Colin Campbell’s site. We use this as the basis for all of our recipes: https://nutritionstudies.org/whole-food-plant-based-diet-guide/
However, you cannot avoid oil 100% but think about it… If you can avoid 90% of your oil by not pouring it in every single pot or pan for every meal, then that is a lot! Oil is full of calories and effect the lining in your arteries over time in a very negative way. If you need any oil I suggest an EVOO spray. That way you get very little and it is hard to over pour it. You can go to NutritionFacts.org for more information: https://nutritionfacts.org/topics/oils/
I don’t think I need to explain processed foods vs real ingredients. After all, Oreo cookies are Vegan!