Kakuros and crosswords are common puzzles you may encounter during puzzle hunts, but they usually come with a twist. For this warm-up puzzle, you need to observe that the kakuro and crossword have the same structure for the blanks that you are required to fill. The intuitive leap here is that the two puzzles are related, with each of the kakuro numbers (1-9) corresponding to a letter that you use to complete the crossword. This is further implied when you try to solve the kakuro and realise that the solution is non-unique, suggesting that there is some other rule to resolve the ambiguity.
The crossword is the easier route by which to enter this puzzle, since most of the image clues are pretty straightforward. You may not be able to identify all the images (e.g. the Pokemon NUMEL may not be familiar to all). In such cases, a helpful tool which you can (and should!) use is a Reverse Image Search Engine. The solved crossword should look like this:
To extract the solution to this puzzle, we solve for the values of these letters using the kakuro. For example, EMAIL sums up to 30 while LIMA sums up to 26, suggesting that the value of “E” is 4. The rest of the logical deductions are left as an exercise to the reader, but the solved kakuro should look like this:
Reading the letters in order of their values (ie. 1=N, 2=U etc.), you get the thematic solution to this puzzle, NUMERICAL, which is a reference to your efforts to deduce the numerical values in the crossword-kakuro.
Some quick solvers realised the extraction mechanism for the crossword-kakuro, and rather than solve for the 9 values of the 9 letters used in the crossword, made an educated guess by using an anagram solver to find the 9-letter word which uses all the letters in the crossword. The only possible word is NUMERICAL, which is a further confirmation to the guess due to its thematic relevance.