you can use https://github.com/mbalestrini/GDS2glTF to generate the glTF file from a GDS file (right now tested and built for SKY130 pdk and small designs)
You need nodejs 16 or higher installed. Get it from https://nodejs.org/en/download/.
Run npm install
to install dependencies.
Finally, run npm start
to start the development server. Go to http://localhost:5173 to see the app.
Run npm run build
to build the app for production. The build artifacts will be stored in the dist/
directory.