In a group stage teams are distributed into several groups and each team plays only the teams in its own group. The draw does the distributing.
How many groups?
You set the number of groups on the Tournament Format screen. The system offers only group counts that fit your number of teams; a count that does not fit cannot be selected.
What if the groups are not equal?
If the number of teams does not divide evenly, groups differ in size — for example 14 teams in 4 groups gives two groups of 4 and two of 3. That is normal, and the system distributes as evenly as it can.
The one thing to watch is that the number advancing stays meaningful for the smallest group: if 3 teams advance per group and one group has 3 teams, nobody is eliminated from that group.
If the number advancing equals the smallest group size, the system warns you but does not block you. That is a sporting choice, not a technical error.
Groups + Knockout
If you want a knockout after the groups, choose Groups + Knockout. You set how many teams advance from each group; the knockout stage receives “group count × teams advancing” teams in total.
Is a second draw made before the knockout?
No. In Groups + Knockout and League + Knockout chains the draw exists only for the first stage. The knockout pairings follow from the standings.