I think I see just what you're getting at.
Lots of Cells. That's quite the eye opener.
So no, you don't get it.
Again, high school level understanding of biology, at the very least, is a common sense prerequisite for trying to 'take down' a biological phenomenon.
As you are in Trump-mode, I think this will be a total waste of effort, so I will not put a lot into it, but here goes...
ALL eukaryotic cells have to perform the same basic functions, whether they are in bananas or worms or humans.
They have to have internal structure - the so-called cytoskeleton. For just one of several cytoskeletal proteins - tubulin - we have 23 genes (and maybe 48 pseudogenes). Another common cytoskeletal protein, actin, is produced by 6 genes.
They have to be able to transport water across their membranes. One way to use this is via a channel protein called aquaporin. There are 14 aquaporin genes.
Name a function that a eukaryotic cell has to perform, and there will be a bare minimum of 1 gene in any and all eukaryotic cells that produces a protein that is involved in that function, whether it is a worm or a bird or a banana.
Getting any clearer at all? Too many big words?
And there is a LOT of stuff IN the cell membrane of eukaryotic cells. About half, by weight, of eukaryotic cell membranes are proteins of various kinds. These include receptors, antigens, adhesion molecules, channels, etc. It is estimated that up to 30% of all genes in eukaryotic genomes encode cell membrane proteins. REGARDLESS of cell type. JUST for proteins in the cell membrane.
Clearer yet?
I know these are not Lego blocks, but this is an issue that you brought up and were clearly uninformed about.
The reason humans and worms and bananas have so many genes in common is because all are made up of cells, and cells all have to do the same basic stuff.
It is like looking at a Porsche and a garden tractor - both need wheels (and the means to connect them to the drive assemblies, etc.), an engine (and all of the things needed for an engine to run), etc. So a Porsche and a garden tractor are going to 'share' nearly all of their parts in one form or another.
Too much info this early in the morning?