GEE - Extract value from image

GEE - Extract value from image.js

var img = ee.Image('LANDSAT/LC08/C01/T1/LC08_044034_20140318');
var dem = ee.Image('USGS/SRTMGL1_003');
var arr1 = ee.FeatureCollection(ee.List([]));


var xy = ee.Geometry.Point([86.9250, 27.9881]);

var p1 = ee.Geometry.Point([142.36083984375, -37.466138602344046])
var p2 = ee.Geometry.Point([143.23974609375, -37.04640889969956])
var pts = ee.FeatureCollection(ee.List([ee.Feature(p1),ee.Feature(p2)]))


print(dem);
print(img);

var date = img.date().format();
print(date);

//var value = img.reduceRegion(ee.Reducer.first(), xy, 30).get('B1')
var value = dem.reduceRegion(ee.Reducer.first(), xy, 30).get('elevation')
print(value);

GEE add map

var im1 = ee.Image('COPERNICUS/S2/20160422T084804_20160422T123809_T36TVK')

// Point
var p = ee.Geometry.Point(32.3, 40.3)

// Extract the data
var data = im1
.select("B3")
.reduceRegion(ee.Reducer.first(),p,10)
.get("B3")

// Convert to Number for further use
var dataN = ee.Number(data)

// Show data
print(dataN)

// Add Layers
Map.centerObject(im1)
Map.addLayer(im1,{bands:["B4","B3","B2"],min:0,max:5000})
Map.addLayer(p)

https://krstn.eu/analyze-Sentinel-1-time-series-in-Google-Earth-Engine/