Bro, you can top one or twice or don’t even have to! AS LONG AS you CAN distribute your potential buds sites (nodes) evenly to the light, you can get multiple major bud sites. You can also LST those potential nodes to let it grow further, although it’ll take more time. Generally, you can top about once or twice (any major branches, you can top and it’ll give you 2 but it’ll take time) and it’ll take about a week or two before it recovers and vegetate fully.