Welcome to ESO. Have fun playing and do it the way you like to! This is the most important thing. You want to be a heavy tank sorcerer, do it.
You always got time to change everythinmg later on and learn new.
So these are only some basic advices which should help you and your other players around:
-Enable the tutorials in the settings.
-Change the color of enemy effects on the groun in the settings to something more visible for you (like pink maybe) and the helpfull fields to green so you know:
pink-> Get out fast!
green->Stay in it and get heal etc.
Watch the enemies and what tehy cast. Try to interrupt them (right mouse button + left) to get less damage.
if you cannot interrupt them, block (right mouse button) to get less damage.
If you interrupted an enemy and it's head is pointing down and they look tumbling, try a heavy attack and they should fall.
Pleay in groups as it's an MMO
Do NOT run and jump around like in other mmos as it will most likely just annoy all other players as youw aste their ressources.
Reason: You get more dmg if you get hit running away from a boss e.g. instead of dodge rolling or blocking.
Healers put heal fields on the ground and if you always run out of it you are wasting their ressources and are killing yourself.
Tanks taunt with sword+board skills and if you run away and not to them with the adds on your back they will just leave you alone instead of trying tow aste magicka for a ranged taunt, so you'll learn how to better play in groups
Support the group by doing lights attacks in between the skills for stamina/magicka ressource gain back (weaving) or doing heavy attacks.
Read the passive skills of your skill trees. They are very powerfull, at least some! Use them (like wear light armor for magicka based playing or medium for stamina based in order to get a good sustain and heal/dmg output).
Advanced:
Only use synergies you really need. If you are at max ressource do not take shards from templars which others could use e.g. Learn what synergies exist by reading skills and morphs of other classes online.