Redo log member and control files at Oracle DB Standard Edition
How many redo log members for each group can I define?


Database Limits

MAXLOGMEMBERS


Default: 2
Maximum Value : 5



  How many control files can I use by using the standard edition (one)?
  I couldn't find this information except, that there can be 8 control
  files at all.


That is correct. CONTROL_FILES


Range of values:1 to 8 filenames



  I've read, that I can have only two archive log destinations defined
  by LOG_ARCHIVE_DEST and LOG_ARCHIVE_DUPLEX_DEST in the standard
  edition (one).


LOG_ARCHIVE_DEST and LOG_ARCHIVE_DUPLEX_DEST are deprecated long ago. LOG_ARCHIVE_DEST_N is available since 8.1 in EE, and 10.1 in SE. You can define up to 31 destinations, but only the first 10 can be local. Remote destinations are not supported in SE.