You might try this one:
https://en.m.wikipedia.org/wiki/File:Kruskal_diagram_of_Schwarzschild_chart.svg
All of spacetime outside of the black hole is in quadrant I. At any point in that quadrant, moving up the page is moving forward in time, moving sideways is moving either towards or away from the black hole (with only two dimensions in our diagram there’s no way of showing east/west or north/south motion so we’ll consider only radial motion).
The scale is chosen so that a flash of light will follow a path along a 45-degree angle: one light-second sideways for every second upwards. (If you’re familiar with the Minkowski spacetime diagrams of special relativity, this is the same concept). Anything moving at less than the speed of light (which is to say everything, including someone falling into the black hole) will follow a path steeper than 45 degrees: less than one light-second sideways for every second forward in time.
The hyperbolas labeled ##r=1.2##, ##r=1.4## and so forth are the paths of objects hovering at a constant height above the black hole. They are hyperbolas instead of straight vertical lines because of the curvature of spacetime, analogous to the way that the straight line path of an airliner appears as a great circle on a two-dimensional map of the earth.
The dashed line is the event horizon, so everything in quadrant II is inside the black hole. The blue hyperbola in that quadrant represents the singularity at ##r=0##.
The squiggly black line with the triangles is the path of someone falling into the black hole.
Once inside the event horizon, everything (including light following 45 degree paths) must eventually reach the singularity.
Light emitted at the horizon stays there forever; anything else on a path at a steeper angle must eventually reach the singularity.