How to calculate land surface temperature from Landsat-7 ETM+ ?

For calculating LST from Landsat-7 ETM+ we would require thermal bands B6 from given satellite imageries. This tutorial will use collection 2 level 1 product with landsat product id “LE07_L1TP_142041_20030311_20200916_02_T1” of acquisition date 2003-03-11.