how to know a non-fraud project?

[Dbamayowa123]

... I expect people to help me identify a fraudulent project before I go back into that dump.

noone can really tell which project will succeed or simply scam from the beginning
and when you joined a bounty project, expect the worst... so don't waste too much resources
my advice, join a project that pays in BTC or ETH on a weekly basis
so when they stop paying, you only lose a week worth of work, time, and resources

How do we get to know those ones?

[Gaselemeg]

Before you join any bounty project you must see if that token have a price in coinmarket or not and you must have an idea if that token gonna be listed on exchange or not

This is not exactly what should be done to be sure that the project is not fraudulent.
As mentioned above there is never a 100% guarantee that the project will be successful even if you spend a lot of time researching it. This is some kind of roulette and you can only reduce the probability of being cheated.