How to derive the reaction function from these provided variables? This is the question. I cant seem to reach a concrete solution because of the scarce information.

Firm 1 spends 2 million, plus 33.33% on advertising what firm 2 spends on and firm 2 spends $7 million plus 12.5% of what firm 1 spends. Draw the reaction functions and label them from the provided information.

I want to know the exact procedure on such problems.
The reaction function tells you how a player in a game reacts to the strategy of another player.

As noted by denesp in the commentary, the statements provided in the question are verbal descriptions of reaction functions. The mathematical description (in millions) is given as follows:

Firm 1:
$x_1= 2 + (1/3) x_2$

Firm 2:
$x_2= 7 + (1/8) x_1$

There is not really any procedure to it, besides rewriting the verbal description into a mathematical description.