Basically, dimensional space is limited by geometries.
You stated yourself the first dimension is a line, second is a plane and the third is a solid.
The fourth dimension is what we currently live in according to modern understanding of physics, which is length, width, depth and a fourth dimension of time.
String Theory (which is what I am assuming you are referring to) is 11 dimensions, with one extra dimension of time.
Something like that.
As such, if you were a fifth dimensional being, you would be unaffected by fourth dimensional time because you are seperate planes of existence involving time.
This applies to a second dimensional being compared to you as well, as your time and his time are different Since time and space are linked, universe also includes time as well, as the two are linked.
In dirt simple terms, higher dimensional beings = number of planes they exist in be it (x,y), (x,y,z) and w,x,y,z) + 1 dimension of time.
The Orville did an episode on dimensions and I highly recommend people interested in the theory to start there, rather then Green's or Neil DeGrasse Tyson's works.