I was told to weld my exhaust for a temporary fix. I was wondering if JB weld would hold for the time being because the leak is getting rather annoying

In my experience, JB Weld, doesn't do well in high temp areas.
Where is the crack you speak of?
If in a...... straight pipe, there are fittings and muffler clamps, made to replace small sections for a few dollars. they fit over one pipe, and inside the other for a leak free fit.

A tin can with the ends removed, and slit down the side,
wrapped around the pipe, and held with hose clamps works for a temp fix too....

If it'* a flange.... better off trying a welder for a few bucks.

If this is the front manifold you mentioned to me there'* probably not a patch possible....you need to pull it and have it welded or put the spare on.

The exhaust seems to be coming from front i haveto do some more exploration. What is the best way to find the leak start the car and feel around?

You could....but you won't have any skin left on your hand

I think to find an exhaust leak, you plug the tail pipe and check for leaks else where.

I started and felt around.. be mindful of how hot and how quick it gets hot.