Electric fields push any charge, moving or not. Magnetic fields are pickier: they only notice charge that is MOVING, and they push it sideways. The magnitude is $F = qvB\sin\theta$ — read aloud F equals q v B sine theta. $F$ is the magnetic force in newtons; $q$ is the charge magnitude in coulombs; $v$ is its speed in metres per second; $B$ is the magnetic flux density in teslas (T); and $\theta$ (theta) is the angle between the velocity and the field lines. Whichever one the question leaves blank is the one you solve for.

The tesla is a big unit and worth calibrating against: Earth's field is about $50\ \mu\mathrm{T}$, a fridge magnet about $5\ \mathrm{mT}$, a hospital MRI bore 1.5 to 3 T. If your answer says the lab bench is running at 40 T, something upstream is lying.

Everything interesting lives in that $\sin\theta$. Fly ALONG the field lines and $\theta = 0$, $\sin 0 = 0$, and the force is exactly nothing. Sit still and $v = 0$, and again nothing. Cut straight ACROSS at $90^\circ$ and $\sin 90^\circ = 1$ — maximum push. Reach for $\cos$ instead and you have claimed the force peaks where it actually vanishes. And one more fact, free now and load-bearing at the boss: the force is perpendicular to the motion, so it does no work. It never speeds a charge up. It only turns it.