Solow model reparations I have the following task:

At some moment of time (1953), the government of a country (Israel) signs an agreement with
another country (West Germany) stipulating that West Germany would pay reparations to Israel
during the following N years. For simplicity assume that N is large enough, that the amount or
reparations is proportional to Israeli output, and that the economy of Israel reaches the new steady
state while the reparations are stil paid.

Need to use Solow model. But I really do not understand what the change will happen. Probably it is the same as an increase in s. Help is needed.
What changes is the macroeconomic identity of the model: from
$$F(K,L) = S + C$$
it becomes

$$F(K,L) + V = S+ C = (1+v)F(K,L) = S+C$$

where $V$ denotes the value of reparations per period, and the last expression reflects an assumption made in the question, that reparations are a constant proportion of domestic output.

"Using the Solow model" means I guess, using the standard Solow model, and so it implies that you don't change its basic assumptions. So there is no distributional issues related to this transfer payment from abroad, while also the savings rate remains fixed, and it is applied to the whole available income (irrespective of how it becomes available). I guess you can take it from here.

PS: It appears interesting to also consider a fixed level of $V$, which would reflect a situation where as time passes and the domestic economy grows, reparations become less important in relative size (which is a "reasonable" scenario, something like "we will help more when you are weak, and as you get economically stronger, helped also by the reparations, our contribution will diminish in relative importance")