I just tried using LWC on my local, but not able to use
<lightning-input />. Is it available for open source? Is there any way to bring prebuilt lightning web components with
lightning namespace to local?
Currently no - none of the platform base component are available for off platform usage. Salesforce is targeting to open Source them in late July (#safeharbor) but their api / shape may also be slightly different than the known one due to missing Salesforce Service - will we see
For the 2nd Question - the only way as of today to use existing base components outside the platform would be via Lightning Out which is a different approach. I would wait those couple of months to see how its evolve with the LWC Framework