mod creation

[Kinddara]

Hello, how are you? I wanted to ask about how to start creating mods. My idea is to design this bike, what programs do you use and if there is any tutorial

It is a motorcycle for riding on the street, but they are assembled and prepared to run on land

original motorcycle: https://motos.mercadolibre.com.uy/x3m/

modified motorcycle : https://www.facebook.com/1183117945133018/photos/pcb.2507622582682541/2507622402682559/?type=3&theater

Racing video : on board https://www.youtube.com/watch?v=uLvIEJEXp7o    , https://www.youtube.com/watch?v=R54Fcjv_tuo


I'm using google translator sorry