As Media Matters described in 2023:

The Constitution has been amended 27 times, always by securing two-thirds support in both chambers of Congress as a first step. Article V of the Constitution provides for another option, though, in which two-thirds of state legislatures call for a convention to consider and put forward amendments. In both cases, any proposed amendment would then need to be ratified by three-fourths of the states. [Mark] Meckler and his organization want to use the second, never-before-used method as a way of fundamentally transforming the federal government.

In theory, any kind of amendment could come out of a convention like the one envisioned by Meckler. In practice, virtually everybody pushing for this unlikely process are right-wing activists with a conservative agenda aimed at limiting progressive elements of the federal government.