You
can check if a player stands on a tile using pixel coordinates.
There are two ways to go about it. Suppose x and y are the position of the tile in tiles, tx and ty are the position of the tile in pixels, and px and py are the position of the player in pixels.
Way 1

Multiply tile x and y by 32 (tx=x*32, ty=y*32)

Subtract player pixel x from tile pixel x and player pixel y from tile pixel y (px-tx, py-ty)

Check if the resulting two values are greater than or equal to 0 and less than or equal to 32 (px-tx>=0 and px-tx<=32 and py-ty>=0 and py-ty<=32)
Way 2

Multiply tile pixel x and y by 32 and add 16 to each (tx=x*32+16, ty=y*32+16) to get the middle of a tile.

Get the distance between the player and the tile ( d = math.sqrt((px-tx)^2,(py-ty)^2) - Pythagorean formula, assume d is distance )

Check if the distance is less than or equal to 16 (d<=16)
Both ways are unnecessarily complicated in this case.