There’s a way to make Nice abs easily ?

Depends on your body type and DNA, but usually it is not fast or easy. One major thing is to change eating habits. Dairy and breads cause belly fat and no amount of ab workouts will give you a six pack. You have to work on getting rid of belly fat before focusing on ab workouts for definition.

Yes, there are many ways, but the simplest is with help. Either supporting your feet to do against weight or have a friend hold you.
A friend is a very good option since you can motivate each other.

No, there is not an easy way to get good and long time results. There are many many ways that you can get nice abs but all of them required time and perseverance, the main one is always good nutrition, if your body is not receiving good fuel the results are not going to be as expected. Also, getting some work done not only for your abs will help out, go for a short run and add some strenght to your routine like core or squats will definitely make a change.

I'm not the best person to ask because I've never managed, but I think the daily seven minute challenge or the four minute challenge plus a good diet should do it… let me know if you succeed!

Nice abs aren’t something that’s easy to get nor to maintain. A lot of conditioning and repetition is required and the right food intake and exercise is also required.

There aren't any shortcuts. Proper healthy diet and exercise. Moves like planks, crunches and leg lifts, you could add weights too for more impact. The visibility of the abs is dependent on the layer of fat in your stomach area. Fairly low body fat percentage is required to actually see the muscles.