Sure thing! Yeah the type I cert is an easy choice, same as 609 MVAC. If you’re considering the trade, you might choose universal (I, II, III) to save time. Exam is longer, closed book, and proctored, but not hard.
Among skilled trades, HVAC is notoriously demanding physically (especially residential, where you’ll spend a lot of time in attics and crawl spaces in hot weather) but consensus on hvac forums is that pay’s good and you’ll never be out of a job as long as you take care of your body.