orbit - How to convert a gravitational force to speed and direction

You must apply Newton's law
$$ mfrac{mathrm{d}boldsymbol{v}}{mathrm{d}t} = boldsymbol{F}$$
which related the force $boldsymbol{F}$ to the acceleration (=change of velocity). Note that positions, velocities, and forces are all vector quantities. Also note that as the objects move (change position), their mutual forces change (both direction and strength).

There is an enormous amound of literature on the resulting orbits for celestial bodies, going all the way back to Kepler and Newton. I suggest you look into elementary books or start with some Wikipedia articles.