Beer foam is gas held in a protein film. You get it when the beer is carbonated, the glass is free of grease, and the recipe has something for the bubbles to cling to.
Wheat malt, oats and healthy carbonation help. A dishwasher rinse full of rinse-aid can kill a head on an otherwise fine ale. So can a glass that last held milk. So can pouring down the side so timidly that you never nucleate a foam.
The old catalogue sold “head” additives next to this joke title. Those SKUs 301 away. You do not need a powder to start. You need a clean glass, a finished beer, and a pour.
If the beer is still green, give it time. If it is a thin lager you fermented hot, the foam is not the main problem.
Serve within the NHMRC guidelines. A thick head is not a smaller drink.