[coole210]

Use PAWN tags around code, please.

pawn Код:

//Code here

The problem you're having for the jetpack code is an error in the special action.

pawn Код:

//You wrote:
SPECIAL_ACTION_USE JETPACK
//Should be:
SPECIAL_ACTION_USE_JETPACK

For your first question, what you're looking for is formatting a string and sending it to all players under the login code.

More information can be found here:

https://sampwiki.blast.hk/wiki/Format