Hello everyone I am new here, and I want to start investing, lately the
DeFi Project is good this year, there are many ubiquitous DeFi projects, both on Twitter and on the Telegram channel, Am I investing in every DeFi Project that can make a profit?

another one is DeFi becoming a promising business in the future?

You should be careful of Defi hype because most projects will soon showcase their true nature which is lack of use case and this will be done after the hype has come down. However, it doesn't dispute the fact there are good Defi projects but scammers likes it when there is too much hype as they can easily bring in theirs and people won't pay much attention because they have channelled their attention on hype rather than use case. So in essence, study the Defi project you want to invest in and make sure that behind the hype there is actually a use case , a good idea and/or working products.