ROTC scholarship and military choice help

Hello I am 17 years old and a junior in high school. Ever since I was young I have always wanted to join the service. My credentials are fairly decent:
-GPA:4.3 (weighted)

-Classes: all honors and AP classes since freshmen year (except algebra 2 sophomore year)

  • Athletics-:JV soccer sophomore year/travel soccer sophomore year, 4 year varsity fencing/captain (including my future senior year), 4 year varsity tennis 2 year captain (including future senior year),

    -Jobs:One summer job at a retirement home

    -Clubs: Business Club, Volunteer Club, Environmental Club

    -Music:4 year trombone player in concert band (including future senior year)
    -SAT: 1640, 1690, 1860
    -PFT: Mile: 6 min 47 sec Pushups: 48 Situps: 62 Pullups: 16
    -Interest for my major is engineering in specific Mechanical, Civil, or AeroSpace

What are my chances that I will receive a ROTC scholarship? I know I am a little behind because I have not talked to any recruiters yet and I am still undecided about what branch of the military I would like to join (I am not applying for a scholarship just “so my college education can be paid”, I genuinely want to serve my country and this is the path that I want to take) When should I start applying? Is it too late because its already half way through my junior year? Thank you for any help.