The statement that is not true is: A healthy ecosystem can support an unlimited number of life forms.
Any ecosystem has its limits. No matter is a healthy, in perfect shape, and very large ecosystem, there's always a limit as to how much life forms can the ecosystem support. If the number of life forms surpasses the ability of the ecosystem to support them, than the ecosystem will crash, be destroyed, and experience a lot of changes, with the death of lot of life forms involved in the process as well.
There isn't such thing as an ecosystem that has the ability to support an infinite number of life forms, there's only ecosystems that are able to support limited number of life forms.
The protostar is a new star that is formed at the end of the Hayashi track and is luminosity temperature relationship of infant stars that are less than M 3. The protostar ends its period and becomes a Tauri star that is extremely luminous.
After which the main sequence of the stars are formed is the next stage in stellar evolution and is dependent on its mass like the sun after this period the star turn red as it has a hydrogen-rich core and it starts to branch out displaying extreme density.
The last stage is the white dwarf star as the star has degenerate and left is the exhaust core which is very dense.