Well, if you want to create a Dapp, there are total six steps involved in this process and they are:
Decide whether to use an existing blockchain or you need to create a new blockchain for your business
Requirement identification
Screen ideas consideration
Project development for Blockchain
Feasible study on the security
Implementation Controlling and monitoring the project
So, these are steps, now to develop a DApp you have to decide on the tools and technologies that you need.
Considering the ethereum, you need the following: you'd need a solidity compiler or IDE (example Remix IDE)
then you need a deveopment environment for which you'd need ganache or equivalent(it is a personal blockchain development tool)
Then you would need metamask to connect to the blockchain, and
finally you have to create a front-end for which you can use basic tools like htmsl, css , javascript, or reactjs.