I have reviewed the attachment and request you to share details of required changes. We have 8 years of experience working on React and technolgoies. We have clients globally. Below are the technologies that we work on:
FullStack: JAVA, Python, Golang, JavaScript, Java, R, Hadoop, Kafka
WebApp Server: Nginx, ApacheTomcat, Node.Js, Weblogic
Spring, Flask, Expressjs, Reactjs
build tools Maven Ivy, Ant
Linux, AWS, Azure
Price quoted is ballpark.