How to build a website builder.

Hello, everyone!

I'm thinking on starting a new project this year.
It'd be a website builder, similar to Shopify.

I'm not a developer, so I'd really appreciate if you can advise me with technologies you'd use, how many team members for a big project like this one, average time of the building....

I know, everything is too generic and relative, but I'd like to have a generic idea for starting to look for what I'll need.

Thanks in advance!