The FCC issues licenses for a particular service (e.g. broadcast, amateur, land mobile, common carrier, etc.). Each service is regulated by a specific part of the FCC regulations (e.g., Part 97 for Amateur Radio Service). These regulations determine the limitations on a licensees use of spectrum. There may also be license specific limitations.
In effect, when you apply for a license in a specific service, you are declaring the type of use you intend. In the Amateur Service, as long as you follow the regulations, you do not normally need to notify the FCC of any particular use as long the use is allowed by Part 97.
Whether you can authorize others to use the frequencies you are licensed for depends on the service. A Land Mobile (Part 90) license will allow for a number of mobile units. The licensee (e.g. a fire department) gets to decide who can operate radios under that license. But the use has to be appropriate to the license (e.g., fire dispatch). An Amateur Radio licensee has no authority to allow others to use radio spectrum. Each operator needs their own license.
License term, power limits, etc. are determined by the service and possibly the specific license. Cost of applying for and getting a license also depends on the service. Costs: Amateur Service - a few dollars for test and time for study; Land Mobile - maybe a couple hundred for coordination or maybe more for big systems; common carrier (cell phone)- Megabucks, maybe Gigabucks (I don't know).
Note: Spectrum auctions mostly (AFAIK) apply to spectrum allocated for common carrier use. And large sums of money are involved.
What you really need to do is think about what you want to do with any radio spectrum, then come back and ask a "How do I..." question.