Last question for now i promise i'm pretty sure the equation you have to use is fgrav=(gm1m2)/d2 but i'm not getting the correct answer

Your equation is perfect.
That's exactly it.

The constant 'G' for SI units is        6.67 x 10⁻¹¹  N m²/kg²  .
Also,  'D' is squared.
(Could one of these be your whole problem ?)

M₁  =  Bob  =  76.2 kg
M₂ = Peggy-Sue = 72.1 kg
D  =  8.54 meters

             F  =  G M₁  M₂    /  D²

                 = (6.67 x 10⁻¹¹ N m²/kg²) (76.2 kg) (72.1 kg) / (8.54 m)²

                 = (6.67 x 76.2 x 72.1 x 10⁻¹¹  N m²)  /  (72.9316 m²)

                 =  (36,645.1 x 10⁻¹¹)  /  (72.9316)        Newtons

                 =        5.025 x 10⁻⁹  Newtons.

      computer notation:  5.025E-9  Newton

           (about  0.000000018 ounce)

Oh !  I just noticed the value of 'G' up at the top of your screen.
OK.  We're all on the same page.

Because the dept in the ocean