Capital loss carry over question for tax

I have a question, I'm hoping someone can answer.
Let's say I have an existing capital loss carryover from years ago of $10000.00

Scenario 1:
Now let's say I sell stock and profit 10000.
Does the capital loss carryover from previous years and the sale this year cancel out?

Scenario 2:
existing capital loss carryover from years ago of $10000.00
Now let's say I sell stock and profit 20000
I also sell a stock for a -10000 loss.
Does the existing capital loss + the current sale loss, negate the profit of the 20k sale?

Last question, I am allowed to claim 3k per year against my capital loss carry over, is this seperate from the above scenarios?

Thank you reddit pros! Sorry for smoov bwain questions

edit: all positions are long