The same as what?
Beths own heads (which I cant see, because they are hidden in some bsa I think)
The same as Beths own heads. You can't see meshes' filenames inside .bsa, but they are mentioned in the Morrowind.esm - more precisely, in the "Body Parts" tab, "Model" column, for Heads/Hair group of records. If you place a head's mesh with the same name and into the same subfolder as in a certain vanilla head's record is written, the engine will automatically take that mesh instead of the one in .bsa, and you don't need an additional .esp to handle it. The problem is, you can only replace existing heads this way, so that if there's six vanilla heads for male Redguards and six heads for females, you can get no more than six/six new heads replacing originals and no bigger variety at all. If you want more heads to choose from, you need an .esp declaring body parts with meshes that Morrowind.esm doesn't know by name.
And NO...there is no ESP-fil or anything else in this pack.
Maybe you just tell the name of the pack or where did you downloaded it from - that way it will be easier to see what you're dealing with.
if you have 1 mesh-folder and 1 texture-folder and NO esp-file, how can one made an esp containing the connection between the NPCs,nifs and dds?
There's no way you can do it in a quick automatized manner, only manually. Open CS, go to "Body Parts" tab, declare a new one, assign a mesh for it, save. Wash, rinse, repeat.