Excuse me if there is another topic on this subject, I tried and not found. If it exists, can delete this.
My question is simple.
I am creating a game that needs an infinite space, creating this infinite space, as there is a limit on the camera viewport?
Anyway, there to establish measures - unit - for the coordinates, such as centimeters, meters, miles, etc?
Thank you and excuse me for my bad english.

There is no such thing as Infinite as a value within a computer (or arguably anywhere else).
You can choose Really big, but you can’t have infinite, especially on something with finite resources (RAM, processing power, etc…)
The larger you make the near/far clipping planes the less detail you get within those planes (things will start to flicker when near each other).
Yes, I understand. I tried using extreme measures and objects began to ‘blink’, ‘shake’. I thought of using small objects, but would need to configure them with very small units which also happens to deform them.
Is there any script that can set the viewport - units of measurement - that is, push the limits of the viewport, (space of the game)?
Well, you can always change Camera.main.farClip and Camera.main.nearClip, however that value uses floats, which have a set amount of granularity. So the more space you want to show the less precise that space is. think of it in terms of percents. An object will blink once it reaches 0.01% of the distance between the near and far plane. So no matter how big or small those planes are if you scale the scene it still won’t fix it.
One option is to use 2 cameras one for near stuff and one for far stuff so that the near camera has a high precision for close objects, and the far camera has less precision, but a huge range so it can show objects far away.
could be more specific in how to use two cameras at once?
thanks