Intersections are the first natural technique people use when solving Sudoku, it's the first obvious method to find missing numbers.
Looking at Block5, where can the <7> go? The intersections of R5 & R6 limit the <7> to R4C4.
Looking at Block4. where can the <8> go? The intersections of R6, C2 & C3 limit the <8> to R4C1.