How do you create tension?

I want to know how to create tension in my story. I’ve already came up with some things such as conflict but I don’t think it’s enough. There is also the usual drama when the LI is jealous of the other LI but I don’t plan on including something like that in my story.
Any tips?

Maybe something dangerous something where gangs and mafias are involved

I’m not sure how helpful this will be, but I do it by having a defined goal, and preventing the MC from having that goal by either having obstacles in the way, or someone (an antagonist, often) working against them.

So, what is your MC’s goal? What do they want to achieve? And why do they want this? How will they get there?

Now, think about all the things that could go wrong. Need to get to a destination? What if the flight is cancelled or the plane crashes? Is it a friend they need to save? What happens when they can’t contact that friend to warn them at a time when the friend is knowingly or unwittingly about to walk into certain doom?

Similarly, how might the antagonist work against the MC? And for what reason? Having an understandable motive and a genuine reason can make a villain effective, rather than just being evil laughter and distant thunderclaps. If the MC needs to get onto the sports team in order to win a scholarship, what if the antagonist wants that same last spot on the team because of pressure from their family?

And finally, one last suggestion is to add a time limit. If there’s a sense of a deadline, where something must happen quickly, where every second counts, then that can add pressure to situations that might not be so tense if you had ages to sit back and mull them over. Timed choices can work well for dramatic climaxes like this.