Contacts and "All Contacts"

Hi, hopefully someone can help before I finally lose the plot.

I have 3 groups in my contacts, "Kids Friends" "Friends" and "Work". I have recently added 2 phone numbers (should be classed as my friends). They do not show up in "Kids Friends", "Friends" or "Work" but do show up in "all contacts".

This just winds me up as the only way I can view it is if I turn on "All contacts"

How can it be part of all contacts but none of the groups???

When adding a contact, how do I designate where it goes?

I've had macs for 25 years, but sometimes I despair....