How to combine so many ffmpeg filters in 1? I dont even know if it's possible, but if anybody could help me would be really great! :) 

So first of all i resize my video with this command:

CODE №1

ffmpeg -i input.mp4 -c:v libx264 -crf 20 -crf 16 -vf scale=750:1334 output.avi


Then i add Gif overlay with chroma key to it like that:

CODE №2

ffmpeg -i input.avi -ignore_loop 0 -i watermark.gif -filter_complex "[1:v]colorkey=0x54FF5F:0.1:0.2[ckout];[0:v][ckout]overlay=x=705:y=25:shortest=1[out]" -map "[out]" output.avi


And then 2 more overlays:

CODE №3

ffmpeg -i input.avi -i arrow.png -i Dots.png -filter_complex "overlay=x=310:y=1230,overlay=x=705:y=25" output.avi


And for the last part i concat vid that i've made with another one like this:

CODE №4

ffmpeg -i "concat:vid1.avi|input.avi" -c copy output.avi


Would be really great if anybody could help me to show few examples on how to merge all those scripts in 1 :) Or atleast №3 and №3. Thank you in advance!
Use

ffmpeg -i input.mp4 -ignore_loop 0 -i watermark.gif -i arrow.png -i Dots.png -filter_complex "[0]scale=750:1334,setsar=1[v];[1]colorkey=0x54FF5F:0.1:0.2[ckout];[v][ckout]overlay=x=705:y=25:shortest=1[gif];[gif][2]overlay=x=310:y=1230[arw];[arw][3]overlay=x=705:y=25" -c:v libx264 -crf 20 -crf 16 output.avi


You should do the concat separately.