Would every user who uses my database have a role? Is it more administrators who will have roles, people who need access to all the tables?
Also, I am unable to offer table-level privileges to a role and offer that to a user.. it just won't work. I have to offer the privileges directly onto the user for them to work. Is that normal? Should I be able to offer table-level privileges to a role or do I have to manually offer each of my users the table level privileges?
Would every user who uses my database have a role?
That depends on how you (or, should I rather say, DBA) set it up.
Quite a long time ago, say until Oracle 8i, there were 2 very popular roles: connect and resource so when DBA created a new user, they simply ran
grant connect, resource to new_user;
and the new_user was ready to go as those roles provided most needed privileges such as create session, create table or create view (check documentation for more info about those predefined roles).
However, it turned out that not everyone should be granted e.g. create cluster (which is one of connect's privileges) so nowadays you should create your own roles, if you want - then grant certain privileges to those roles and, finally, grant roles to your users.
Another option is to keep .sql scripts for each of your users. That script should contain list of privileges granted to those users, separately, which means that you shouldn't granted anyone privilege they don't really need.
I am unable to offer table-level privileges to a role and offer that to a user. it just won't work. I have to offer the privileges directly onto the user for them to work. Is that normal?
It works, but not everywhere. Those privileges (the ones granted via roles) won't work in named PL/SQL procedures (i.e. stored procedures, functions, packages). If you have to use those tables in them, yes - you have to grant privileges directly to each of those users.
As opposed to named PL/SQL procedures, privileges granted via roles will work in anonymous PL/SQL blocks or at SQL level.
If you're wondering why would you use roles at all, then, the answer is my first sentence: it depends.