Healer or tank, melee or ranged - that is the question…
No!
No more that question. If you cannot choose between two (or even more) classes, the correct answer is only one.
Level them all!
But, you may oppose, “I have no time.” Well, then I have excellent news for you. Leveling several characters takes less time than leveling one. It is called multiboxing.
You make two characters, start two WoW clients, load these characters, and bind their spells to the same keys. Then just duplicate key presses via any hardware/software to clients and play both characters at the same time!
Besides the main goal (you get all the classes you want), such an approach gives you additional benefits:
- a lot of fun
- faster leveling (especially in Classic)
- new expressions and feelings (especially if you get used to WoW)
- increased PvP power
- better farming capabilities
So I hope this helps you not to have pain when choosing a class.
If you need more info, there is already a topic with some multiboxing description and discussion:
https://us.forums.blizzard.com/en/wow/t/for-newbies-what-multiboxing-is/