Getting error for Drupal 10 installation.

Not sure but it seems you are trying to install older version of bs_base which requires D8 or D9. Make sure you are installing the latest version of bs_base which is beta6.

Ah I see now your composer is also using bs_lib dev version which is wrong - maybe that is blocking your composer install. Make sure that you are installing bs_lib 8.x-1.0-beta4 version.

You could try -W option that composer is telling you and see will that help.

I am installing using composer as composer require 'drupal/bs_base:^1.0@beta'
and getting above error.

Go to your composer.json and change minumum-stability value from stable to dev, so instead

    "minimum-stability": "stable",

you need to have

    "minimum-stability": "dev",

This is needed because bs_base and bs_lib versions are still in beta release.

Thank you @pivica
It is working for me now.

Great.

Automatically closed - issue fixed for 2 weeks with no activity.