Some Navigation links not working in React App

[andrewjoemon]

This is my react project. https://andrewjoemon.github.io/react-app/ Firstly I want to mention that everything works clearly in local host. Its github hosting which is facing issues. Tabs like home and about work but temp tab does not work. It shows error 404. Also on default, when the website is opened, it should show create resume button also and welcome to my page (which is working when I click home tab but that's not enough) but it doesn't. Why is it so? Can anyone help to solve this issue.