If you have been accepted by a university in the US, you must apply for the student visa from within your own country. Your visa interview, etc, will be conducted at the US consulate nearest your home. You cannot change status from tourist to F1 within US.
The 5-year (or 10-year) multiple entry visa is solely for tourism. You are limited to a maximum of 180 days upon entry (authorities will set some limit of time within the max of 180 days, depending on your funds, etc.), and a maximum of 180 days out of any 365-day period. You are NOT allowed to stay for 5 years, only periodic visits solely for tourism.
If you try to change status while within US, you can be deemed to have committed visa fraud, intent to remain, and have your tourist visa revoked & be permanently barred from US. If you are a legitimate tourist, you visit & return home. That's it! You do not apply for jobs or school or do anything whatsoever to indicate any intent to remain in US.