The most common things (tools, libraries, framework) you and your team will need to have to get started are
A Laptop/Desktop Computer - Your choice of computer should be guided by the following
An IDE - There are quite a number of awesome IDEs out there. I use and recommend VS Code . Make sure you check out VS Code extensions for better coding experience.
Libraries & Frameworks - Depending on the language(s) you and your team code in, amongst many other things, you may have two or more libraries or frameworks you will be working with. I write mostly in javascript (and Typescript) so my line ups are
Source Code Management - I recommend git, and GitHub .
CI/CD Tools - There quite a number of them out there. GitHub offers an elegant solution, so does CircleCI , Travis CI , and Jenkins .
Cloud/IAAS Account - I use Google Firebase , and Digital Ocean for staging/production mostly. I recently launched a product on AWS , and the experience was an interesting one. I'd recommend them.
Team Communication - I would recommend email, Slack, and Trello
The list is not exhaustive, however, it will get you and your team started. I hope you find the information useful.
All the best!