How to download DEM data || Downloading SRTM DEM || Digital Elevation Model download from USGS
For more tutorial click on the links below: Land use/land cover classification in ArcGIS:    • Supervised Classification of LANDSAT ...  

Supervised image classification:    / watchv=ilt7vs7rshk&t=943s  
How to download satellite imagery:    • How to Download Satellite Imagery || ...  
Digitization in ArcGIS:    • How to digitize in ArcGIS || Digitiza...  
Georeferencing in ArcGIS:    • Georeferencing in ArcGIS || How to Ge...