Your motherboard has two fan headers (CPU_FAN and CHA_FAN). Without using any Y-splitters or fan hubs, the maximum fans you can install is 2 (one fan in each motherboard header).
If you use Y-splitters or fan hubs, the maximum number of fans you can install will be dependent on the fans' total ampere/current draw. Each fan header of your motherboard can provide a max. of 1A current, unlesss stated otherwise in your manual. So, you have to check each fan's current draw rating (which is usually provided for on the fan's sticker or box). The total current draw of all the fans connected to a single header should not exceed 1A (or for headroom, at least max. of 75% of 1A or equal to ~0.75A to be safe).
For example, you have a fan that...