You can change nay paramaeters on the right then click start simulation when you want to run it.
You can press any buttons if you want to toggle them on/off

Data

Mass of Star(10^30 kg) 5.00
Radius Of Orbit(AU) 2.0
Mass of planet(10^23 kg) 1.00
Velocity of planet(m/s) 0
Orbital Period(yars) 0
Mass of Star (10^30 kg)
0.1
5
10
Radius of Orbit(AU)
0.1
2.5
5
Mass of Planet(10^23 kg)
0.1
5
10
Speed up factor(time 10^6)
1
5
10