https://code.visualstudio.com/

Offline You can't and even if you installed it somewhere and started using it on your pc without an internet connection you still need the language extensions which you wont have so my advice is buy a 100 birr card buy like 10 internet packages and open your hotspot then tell your computer to take it easy on the data usage and download what you need

https://www.youtube.com/watch?v=A8fc5NlMDKE ይሄንን እይና ከዛ ከስር ሊንክ አለልህ እሱን አውርድ ኢንተርኔት ቤት ከዛ ቪዲዮውን ተከትለህ ተግብረው ይሰራል (አይ ትራይድ ኢት ሎንግ ኤ ጎ ኢት ዎርክስ ፋይን)

Ke sew tekebel softwarun ena install just like u install other softwares