How to manage full stack project with many number of developers?

We have a team of developers currently working on a full stack project. Here are the technology stack we are using for the development part.

• Frontend - Angular
• Backend - NodeJS / Java Spring Boot
• Database - Postgresql

We have 3 developers in front-end part and another 3 developers in backend part.

Now we have a huge problem with connecting front-end and back-end.

Because backend (RestAPI & Database) is working fine in backend developers machine. But frontend developers can't access that RestAPI and Database because it is run inside the local machine.

So we need a good solution to resolve this issue. We need to access Back-end (RestAPI and Database) from front-end developers machine and also we want to update immediately after any changes done by back-end developers and that should be available to front-end developers as well.

We need more reliable and standard mechanism or technology to resolve this issue.