For 10 x 10 ft room first calculate the volume and then find the no. of brick with the following method Room walls volume can be found by Centre line method or long wall short wall method.
Let us take an example for 10 Cu.m masonry Size of bricks 230 x 115 x 75 mm Volume of brick 1.98 x 10-3 Cu.m Adding cement mortar (Thickness 10mm) 240 x 125 x 85 mm Volume of new brick 2.55 x 10-3 Cu.m No. of modules =10/2.55 x 10-3 = 3922 No. Adding wastage 12% =3922 + 12% = 4393 No.
Here module is brick along with the cement mortar on all side. Now, this is for 230mm wall, this method is not applicable for partition wall, as it is measured in sq.mt35 it is having different method. Hope this help!