Steps for existing spartacus sites

which of the steps in https://developer.moovweb.com/guides/spartacus#section_building_from_scratch are relevant for an existing Spartacus sites?

In my Spartacus project,

backend: {
    occ: {
      baseUrl:

src/app/config/app.store.config.ts

not app.module.ts as mentioned in the docs

what should the value be for

+ context: {
+   baseSite: ['electronics-spa']
+ },

for an existing site?

It should be possible to leave it empty.

Exactly the same as what?

As much as I understood looking at some apps I found out that:

  1. It can be empty
  2. It can be random string
  3. It should match the store key name.