In fact this Gota.io is the same Agario, but with advanced features. The game has a lot of settings, your cell moves faster and can be divided into three parts.
So rules in Gota io are the some. You should eat colored dots and cells of other players to gain as much mass as possible. The larger your cell, the easier it is to eat other smaller cells. But the speed becomes slower.
What to do? For this, the game provides an opportunity to split your cell into 3 parts. Be wary of green spikes if your cell is already very large. But while you are small they are not dangerous for you. If you even ran into a green spike, your cell will split into a lot of small ones and you will need time until all the cells go into one big.
As in many similar games, you can choose a beautiful skin, change the color, remove your nickname and so on. You can choose the server that you like, there is also a Beta server on which 1000 people play at once and of course Experimental server.