1) is it true that Pascal has no modules, no type safety for dynamic records, no garbage collection?
This all depends on dialect. Classic Pascal afaik had more safety for dynamic records than Free Pascal/delphi, in the sense that if you accessed a field that wasn't in the selected form of the dynamic record, it would generate a runtime error.
Classic Pascal has no units/modules, most surviving pascal do in one form or the other. Free Pascal/Delphi modules are a bit more limited than Modula2 modules though.
2) is Modula-2 dead? If not, why it is not more popular, since (in theory) is more powerful than Pascal?
There are some compilers in maintenance mode afaik, and GNU M2 is somewhat developed still. I still monitor comp.lang.modula2, but the flow there is extremely low.
Declaring it dead is a political statement, but it is several orders of magnitudes less active than just Free Pascal, let alone other major Pascal environments like Delphi.
3) is it true that Component Pascal is the most active dialect of Oberon(s) ?
CP is related to Oberon. It was afaik one of the first non microsoft .NET implementations. (probably because it had a java version before?). How active it is I don't know.
4) is it true that Oberon-07/11 is mainly for embedded systems?
No idea, I never considered Oberon very practical.
5) what is, in gross terms, the relation --applications, features and generality wise-- amongst FreePascal, Modula-2, Component Pascal ?
Free Pascal inherited some form of module system mostly directly (but not the same) from M2, and then there is Niklaus Wirth. Modula2's parsing
is typically also based on the same principles (LL, recursive descent) as Pascal.
There are some superficial syntax similarities, but that is not unique (e.g. C has FOR and WHILE too)
That's about all I can think. Very little practical, nearly everything historical. No real relation to Component Pascal at all I guess.