What's a good torque wrench to get?

Honestly, if you are just getting a torque wrench for spark plugs (and any other BASIC projects at home) any brand will do. Just make sure it has the torque range you need.

I recommend "click type" because they are easy to operate correctly, and easy to take care of. Seriously, read the manual that comes with it, and follow the steps everytime. If you do this, it will last you a long time.

I bought my two torque wrenches from Harbor Freight for about $10 each. Torquing frame bolts or spark plugs? No problem. Would I use them for valve train or engine internals? Absolutely not.

If you don't want to go the cheap route, go to any big box store like Home Depot or Lowe's (US) and anything name brand will do, as long as it has the torque range you need.

I just use my regular wrench and say "click" out loud when it feels nice and tight

As usual, Project Farm to the rescue

I'm a fiscally conservative (read: cheap-ass) diesel technician. Most people I work with have snap-on, matco, mac, or cornwell, but someone I work with said he has a Quinn at home that worked great so I got one and have had no issues with it.

Any of those suggested here are good just pick one to suit your budget. The most important thing is to make sure it comes with a calibration certificate to say that 30Nm is in fact 30Nm. If you're in the trade then get it calibrated yearly.

Gedore TORCOFIX wrenches are excellent, but a bit spendy.

Want to go really cheap and tighten a broad range of newton meters? Use a wrench, a luggage scale, a calculator and science lol

https://www.engineeringtoolbox.com/torque-wrench-luggage-scale-d_1909.html

People use this trick to calibrate torque wrenches... I use it to tighten my motorcycle brake caliper bolts

I can't give you advice on the topic, but how related is your username to your question?