Gdddk

I am facing problems with the following diagram given into image:

How may I code for it in overleaf code? by using tikz package

begintikzpicture 
draw[black, thick] (0,0) rectangle (3,2) node[pos=.5] text;
endtikzpicture

This is to give you a start. For each of the features you will find many posts on this site, perhaps not yet in precisely this combination.

documentclass[border=3.14mm,tikz]standalone
usetikzlibrarychains,positioning,calc,shapes.geometric
begindocument
begintikzpicture[font=sffamily,boxed/.style=minimum width=3cm,minimum height=2cm,draw,thick] 
 beginscope[local bounding box=upper]
 beginscope[start chain=1 going below,every join/.style=-latex,thick,frm/.style=boxed,on chain=1,join]
 node[on chain=1](n0) Training data set;
 node[frm](n1) abc;
 node[frm](n2) abc;
 node[frm](n3) abc;
 node[frm](n4) abc;
 endscope 
 node[boxed,right=3cm of n1] (n5) abc; 
 node[boxed,right=3mm of n2] (n6) abc; 
 node at (n0-|n6) (n7) Testing data set;
 node[boxed,right=1cm of n3] (n8) abc; 
 endscope
 draw let p1=($(upper.east)-(upper.west)$) in 
 node[boxed,below=5mm of upper,minimum width=x1] (n9) abc;
 node[below=3mm of n9,
 trapezium,trapezium left angle=60,trapezium right angle=120,
 minimum width=3cm,minimum height=1cm,draw,thick] (n10) abc;
 beginscope[every edge/.style=draw,-latex,thick] 
 path (n7) edge (n6) (n6.-140) edge (n9.north-|n6.-140) 
 (n1) edge (n5) (n5) edge (n9.north-|n5.south)
 (n6.south-|n8) edge (n8) (n8) edge (n9.north-|n8.south)
 (n4) edge (n9.north-|n4) (n9) edge (n10);
 endscope
endtikzpicture
enddocument