Agree with @Recapitated. CP 160 is when gear matters. Additionally, I'd wait until CP 300 to tank the lower vet dungeons simply because you won't have the resistances necessary. But have at it in those normal dungeons.

One other piece of advice, you should level your tank skills as a DPS. It sounds completely backwards, but tanking to level tank skills is a waste of time, primarily because it takes so long to kill things if not spec'd as a DPS. Obviously skills like S & B or destro staves need to be levelled while equipped with those weapons, but the majority of tanking skills do not. So you can run as a dual wield or 2H or even a magplar as long as you have a decent combo of DPS and tank skills on your bar.

But, more importantly, as a DPS you will learn mechanics in dungeons, see where the best place to put adds and bosses are, and where you want the DPS to stand. Most are very straightforward: turn boss from group, DPS stack and burn. Others require adds to be pulled in, the boss to be moved, the tank to be wary of one-shots and interrupts, etc. I think its easier to learn this as a DPS while watching or playing with an experienced tank.

EDIT: You might find that you don't like tanking after all. So then you'll have a fully spec'd DPS to run with. Or maybe convert your templar to a healer. Skill points are so easy to acquire in this game. My Stam DK, Stam Necro, and even my Mag DK can all be quickly turned into DPS, PVP DPS, and PVE Tanks as they have all the necessary skills levelled

As of this patch, because of Set Collections, you can craft gear that drops from dungeons, overland etc at the cost of 25-75 transmutations stones. But you have to have gotten that drop bound to your character before, meaning you need to have the item in your inventory then either wear it, deconstruct it, or sell it to a merchant. (Decon is usually better). To reconstruct the item you'll also need to have it research in the trait you want, so you should hurry up and research sharpened, precise, infused weapons and divines body pieces. Those are the priorities. It's best to pick one character who will be your crafter so you don't have to invest skill points into crafting across multiple characters

The transmutation stone cost depends on how many pieces of the set you've collected. What this means is whereas before, getting a good drop on a <cp160 character was a complete waste and now it's not a complete waste, even though it's better to get that drop on a cp160 character, at least you'll be reducing the cost of crafting the gear you want.

What I would do now is level one character to CP160, but it won't hurt to do a random normal on each character and if people running with you are willing, take their gear drops and deconstruct them so you can reconstruct them later. You'll also get a decent amount of transmutation stones to work with and that will help in the long run. Make sure you read about Set Collections so you understand the whole thing.