Not really, but
1) You can use pe scripts to load the DLLs referenced by the main PE file
2) You can use File-Load additional binary file
3) Ilfak has some more comments on this.
are you talking about using IDA in debugger mode ? and what would you wanna do ? note that IDA is known as "the" Static analysis platform and its core is a disassembler and binary analyzer so basically when you say IDA... people start to think of static analysis stuff e.g what igorsk just mentioned . you should make your questions as clear as possible ; and no IDA cannot debug two different local executables simultaneously in a single instance , but you can run several IDA debugger sessions in different instances , besides if you are into debugging you better take a look at Immunity Debugger here at the beginning .
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