You don't necessarily need to go to college for office admin roles however, college can show your employers that you're able to apply yourself. It teaches you skills around responsibility, problem solving and time management.
Starting out in a admin role within any company is a great opportunity to see how a business works and if there's any roles within it that you'd be interested in pursuing through study. Alternatively, you might really enjoy the admin role so much that you'd rather progress in that area instead.
In my opinion, the best admin roles can be found in the emerging tech market. They're most certainly the most fun in my perspective and have the best company culture. Choose an industry that interests you and look for admin roles within it - legal, finance, tech, medical etc.
You'll need to search "entry level" when you're looking at job ads online. If you don't have any prior office admin experience, you may have to start in an entry level reception or data entry/filing position at first. Any prior customer service skills are a plus, as you're often speaking to people and answering phones.
Skills you'll need:
-Customer service/interpersonal skills
-Basic Typing/Presentation/Spreadsheet knowledge
-Organised and presentable
-Basic computer knowledge