Until end of turn, target player can't cast instant or sorcery spells, and that player can't activate abilities that aren't mana abilities.
Draw a card.
Abeyance does not affect abilities which are not activated, such as static abilities and triggered abilities. It also doesn't stop the declaration of attackers or blockers.
Abeyance never prevents mana abilities from being activated.
Abeyance prohibits activated abilities of cards which are not on the battlefield.
This can't be used as a counterspell. It will have no effect on spells which were on the stack when it was cast, nor on those cast in response to it.