My goal is to download the monthly mean Red band (B4) from Landsat 8 for the year April 2013 to December 2022 (total 117 monthly mean images) using Google Earth Engine (GEE). For this reason I am using data from the Collection 2, surface reflectance products (https://developers.google.com/earth-engine/datasets/catalog/LANDSAT_LC08_C02_T1_L2). I have very little knowledge of GEE so what I am doing so far is change manually the months and then export each monthly image, like so:
var landsat = ee.ImageCollection('LANDSAT/LC08/C02/T1_L2')
Map.centerObject(table);
//Create mask function
function maskL8sr(image) {
// Bits 2, 3 and 5 are water, cloud shadow and cloud, respectively.
var cloudShadowBitMask = (1