What is lnsolve.com ?

It's a forum for asking and answering questions!

How can I earn bitcoin on lnsolve.com?

You earn bitcoin by answering questions. Once the solution is accecpted you're automatically paid the bounty in bitcoin.

How can I withdraw the bitcoin I've earned?

Your bitcoin can be withdrawn via the lighting network.

Who puts the bounty on the problems?

The poster of the problem sets and pays the bounty

How is it different from other platforms?

In other forums there is no incentive for people to answer questions. Which is why a lot of questions are left unanswered.

In lnsolve.com people get paid in bitcoin when they answer correctly. So there's a strong incentive to answer questions.