What happens if kicks from the penalty mark are drawn indefinitely?

Question

In football, what is the rule when both the team score equally indefinitely in kicks from the penalty mark?

Do they keep going and going or will they toss or something to decide the winner?

Answer 1

Yes, they will continue, even if all players have taken a penalty kick. The procedure is described e.g. here on Wikipedia:

10. If after five rounds of kicks the teams have an equal number of successful kicks, additional rounds of one kick each will be used until one team scores and the other misses. This is known as sudden death.

Answer 2

The Laws Of The Game are unambiguous. Law 10.3, Kicks from the penalty mark, says

If, after both teams have taken five kicks, the scores are level, kicks continue until one team has scored a goal more than the other from the same number of kicks

There is no exception and no other criteria. The game ends when one team has scored more than the other, no matter how long that takes. Competitions are not permitted to choose any other methods except those in the laws, so changing the process would be illegitimate:

National FAs have the option to approve different modifications for different competitions - there is no requirement to apply them universally or to apply them all. However, no other modifications are allowed without the permission of The IFAB.

emphasis in original.