The equation you would use is $$v=v_0+at$$ Note that the constant acceleration can be expressed as $$a=\frac{F}{m}$$ so $$v=v_0+\frac{F}{m}t$$ and so $$F=\frac{m(v-v_0)}{t}$$ and if the initial velocity is zero then $$F=\frac{mv}{t}$$ So if $t=2s$ then $$F=\frac{mv}{2}$$

The equation you would use is $$v=v_0+at$$ Note that the constant acceleration can be expressed as $$a=\frac{F}{m}$$ if the object has a mass $m$. So $$v=v_0+\frac{F}{m}t$$ and so $$F=\frac{m(v-v_0)}{t}$$ and if the initial velocity is zero then $$F=\frac{mv}{t}$$ So if $t=2s$ then $$F=\frac{mv}{2}$$ If your target velocity is for example $10ms^{-1}$, then $$F=5m \ \text {Newton}$$