WoW Forever talent points: levels, ranks and prerequisites

Without the Talented Legacy perk, a level 25 Mage has 16 talent points. Points start at level 10, one arrives each level, and the total stops at 51. Open the Mage talent calculator and set the level before you spend anything. A rank that does not fit the budget, or a talent whose prerequisite is missing, is rejected.
How many points does this level give?
Count level minus 9, then stop at 51. Level 10 has 1 point. Level 20 has 11. Level 25 has 16. Level 60 has 51. Every class on the planner uses that start, that cap and level 60 as the top level.
Main and Alt each keep their own class talents. Switching the character control does not empty the other character. Talented can move the first point earlier, and only for the character who spent that perk. Rank 1 starts points at level 9, so the same level 25 Mage has 17 points. Rank 5 starts them at level 5. The ceiling stays 51: a level 60 Mage with Talented at rank 5 still has 51 points, not 56.
What has to be learned before Arcane Meditation?
Arcane Meditation has three ranks. It requires Arcane Concentration at rank 5, and 15 points already spent in the Arcane talents that precede it. Those 15 include the five ranks of Concentration, so you still need 10 more in the other preceding Arcane talents. Meditation itself costs a point after that gate. Points in a locked talent cannot count toward unlocking that same talent.
At level 20 the Mage has 11 points. Eleven cannot cover a 15-point gate, so Meditation stays locked. At level 25 the 16 points are enough: 15 in the preceding Arcane talents, then one rank of Meditation. A point spent in Fire or Frost does not fill that Arcane gate.
What does the next rank say?
Rank 1 allows 17% of mana regeneration to continue while casting. Rank 2 allows 33%. Rank 3 allows 50%. Inspect each rank before learning it: the values are 17%, 33% and 50%, not an even increase you can estimate between ranks. Learning rank 2 requires the first rank as well.
Some talent descriptions are incomplete, but the linked spell can still answer the question. Arcane Blast is one example. Its spell ranks are listed at levels 20, 30, 40, 50 and 60, and the talent also asks for 10 points in the preceding Arcane talents. Read the spell for its damage rather than treating the missing talent description as no effect. Presence of Mind, one row deeper, names its own gate: 20 points already spent in the Arcane talents that precede it.
How do you share the build you are looking at?
Use Share link after the ranks are right. The link keeps this character's talents and the other character's choices, including Legacy perks, recipes and equipment. Opening it restores that plan. If the link no longer matches the talents on the page, the page keeps the plan you already had.
Follow the spell or Legacy link from the calculator when you want to inspect the next piece. The allocation comes with you.
Set the earlier levels in Legacy points for a main and an alt, read exact spell numbers in spell ranks and level requirements.