ffmpeg to embed subtitles [closed]

Intend to collect some stuff for academical purpose, to introduce in a seminary.
Attempting to embed subtitles in the frames of a mp4 file, below some commands that i’ve been tried out:

ffmpeg -i input.mp4 -vf subtitles=subt.srt output.mp4 

ffmpeg -i VID_20230918_161450.mp4  -f srt -i subtitles1.srt -map 0:0 -map 0:1 -c:v copy -c:a copy -c:s mov_text output.mp4

ffmpeg -i seu_video.mp4 -vf "subtitles=seu_arquivo.srt" -c:v libx264 -c:a aac -strict experimental -b:a 192k -y seu_video_com_legendas.mp4

…according to the major issues/responses/or “oracles” around the web.

With the first one, i got as response:

[AVFilterGraph @ 0x557e87157240] No such filter: ‘subtitles1.srt’ < br/> > Error reinitializing filters!

The second creates the output.mp4 but it comes without subtitles.

The third, surprisingly, was well succed, for a moment. I will explain:
as i’d to translate the video, I wanted to conduct some tests… At the first, the mp4 had a little more than few seconds, which was well succed. Calling the purposed video, it brokes:

[Parsed_subtitles_0 @ 0x558e29010280] Unable to open subtitles1.srt

…subtitles.srt which is exatcly the same file tried firstly.

“Phantonessly”, both of they, the test and the purposed video ones, doens’t work anymore.

I made up some changes here and there, but for summarize is it.
The SRT file have none syntax erros, as you can see:

1
0:0:0.000 –> 0:3:0.000
test, teste, teste, á?

It’s for academical purposes.

Thanks.