I am not getting any output in the Subset_soil_param.txt file

[Baloch]

not tested but

with open('Grid_cell.txt') as f:
    grid_cells = [line.strip() for line in f]
 
with open('original_soil_param.txt') as f, open('subset_soil_param.txt', "w") as sub_f:
    for line in f:
        cell_id = line.split(' ')[1]
        if cell_id in grid_cells:
            sub_f.write(line)

Buran, man it worked, thank you so much.