Usually it's a front-end project, so I'll pick my framework. Usually React, although I've been wanting to try out Svelte.
Next my bundler, which used to be create-react-app, or some other Webpack wrapper. Today, Vite is the best choice because it works pretty well without much configuration, and it supports all of the major frameworks which is quite nice.
I'll be sure to install and configure the TypeScript compiler, which is usually copy-pasting from a template. I always make sure to target the latest well-supported version of JS and use ESM modules, because I like being on the bleeding edge.
Next up I setup linters -- eslint + prettier. They do a good job. I have to configure eslint so that it plays nice with Prettier, and I also have to configure eslint for TypeScript and add any other plugins that the project might need, e.g. those for React. I usually like to setup some kind of pre-commit hook to run Prettier and eslint before committing, which saves time.
Additionally, I always install my IDE extensions and try to create a .devcontainer file or add list of recommended extensions so that both myself and others can setup their IDEs in the future. I tend to not configure eslint much and just use off-the-shelf configurations because I don't care about the style, I just want consistency in the code and mistakes to be caught.
Next up I setup my unit tests, usually jest or vitest or similar. Lots more configuration for TypeScript and whatever, and also usually a set of eslint rules.
Then I want a CSS framework. I like tailwind, so I install that and styled-components and twin.macro so that it all works nicely with React. Fonts and icons are often needed too, so I install a plugin for Google Fonts and whatever font library.
Anyway, after about a day of doing the above I'm ready to program. Why is it so much work? Why isn't there something that just works for 90% of the use cases? So many people are using Vite + TypeScript + [React|Vue|Svelte] + [eslint|prettier] + [tailwind|bootstrap] + [jest|vitest]. Why isn't there some non-configurable library that just does everything for me?