First you need to get a test setup for checking compression on a diesel engine.
Here is a link to a comparison article on testers. You can probably get a free rental kit from the automotive supply store?
Boost your diesel engine's performance with the top compression testers on the market, but which ones reign supreme?
themotorguy.com
Make sure it has a fitting that fits your engine using the glow plug hole (easier) or the injector (more difficult).
I assume you have some history with the tractor so share a little more please. Has it been sitting for days, month, years? Do the glow plugs actually work? Was it running yesterday, last week, 10 years ago? What did it do before you used the starting fluid?