Hello, So I recently bought a 1996 240sx that has an SR20det engine swap from a friend of mine that was moving to another state. Now I know these cars are pretty much high maintenance and can have a lot of issues and I don't have a lot of experience working on cars. But, I have friends and family that are and they are willing to help me learn. So with that being said, my car is in decent condition, no rust, just a few dings and scratches along the body, its one solid color so that's good, interior isn't terrible but there are some cracks on the dash, and the only issue that I know of is an exhaust leak. So I know I need to get that fixed. I just need some guidance on what I should do so if anybody has some suggestions or a source that they can link I would greatly appreciate it. Thanks!

Exhaust leaks are pretty straight forward... you just have to get under the thing and find it, then either patch up whatever hole is there, or replace gaskets/resurface flanges, etc.

I would think any other maintenance related questions (like what's due and when) should be directed at your friend that sold it to you. He would know when the last time specific maintenance was performed.

Find and nice winding road and enjoy driving it!
If it seems to "run fine" you could do nothing but where its the fun in that?
If you don't get any information from your friend that sold it to you, I'd replace the coolant, oil and filter, spark plugs.
I'd also take a really good look at all the vacuum lines.
As for discovering the exhaust leak, a shop-vac or leaf blower in the tail pipe while you are spraying soapy water on a COLD exhaust will make the leak bubble up pretty fast.

Then it's a matter of start buying tools

Thank you guys for the feedback! This definitely gives me some direction on where to start!