Need help with backend API for a Simracing championships platform

Hello everyone, i am front-end developer with 2+ years experience. Now i am working on an the project that will allow e-sports players to create, manage and participate racing championships.  

https://github.com/SUVORKIN/racing-tournament

The technologies is Vue.js, Vuetify.  

Some part of frontent is ready but i have no possibilities to learn back-end at the same time. I’m asking for help.

I would make full rest api spa, so we need to realize some methods on server to store and return simple groups of data.

Sim-racing would be very popular as an e-sport discipline very soon, but at this moment in the Internet there is no analogs to my idea. Every championship and every organization that estate championship uses very primitive way to manage it - Forums or social networks, google docs for store results. I want to create an application that will give users an oportunity to store their results, statistic, history of participation, follow to race calendar, siple way to join the championship and quit. There is alot of similar services for CS, Dota, but no one for racing.