If you want to refresh yourself on the original before checking out the sequel, you have plenty of options.
How the Original 'Top Gun' Producers Assembled Tom Cruise, Tony Scott
17 callbacks to 1986's 'Top Gun' to watch for in 'Maverick' - Los Angeles Times
How to watch Julian Sands' most notable movie roles - Los Angeles Times
Top Gun' Stars Then & Now: Photos Of Tom Cruise & More – Hollywood Life
A comparison of the Top Gun soundtrack between Vinyl (1986, Japanese, 2016), CD, SACD, Streaming Qobuz and Tidal. : r/audiophile
Tom Cruise, 'Top Gun: Maverick' and Uneasy Echoes of Hollywood Past
Maverick (TV Series 1957–1962) - News - IMDb
They're not Maverick and Iceman from Top Gun. They just look it
Top Gun' and Tom Cruise return to the danger zone
Maverick (TV Series 1957–1962) - News - IMDb
Kenny Loggins' 'Danger Zone' Will Appear in 'Top Gun: Maverick