several surnames in my batch have +o after it. What do I do in that case?
You ignore the +0 and just index the surname.
If you need more help, please include your batch number (the numbers in parentheses) and we can better respond.
From the What To Remember AboutvThis Project section of the Project Instructions:
+o or &o, can mean “and others.” You might see &sp for “and spouse.” As the instruction and @slotbuddy said, those qualifiers/descriptors don’t get indexed.