infinity is a range of number.
i don't call it concept, but i call it a range of number in "series".
to make it physically appear so you understand how i view it,
i use an example = computer memory address.
each address is real, they are able to store your bits.
now we come to a concept, "place to hold a number", it is unseen stuff, but maybe mathematician will discover them soon or they discovered
a number need a placeholder in order to exists.
what infinity got is a range of place to hold any number but it hasn't yet hold any number.