Some men affected by infertility will have a complete absence of sperm in the ejaculate. This is called azoospermia. It may be that sperm production is normal, but there is a blockage preventing the sperm from entering the semen during intercourse so conceiving naturally is not a viable option.
In your particular situation, based on your hormone tests and examination, the cause and diagnosis will be ascertained. The appropriate surgical technique will be applied. This may involve collecting sperm directly from either the epididymis (collecting duct) or testicles, or sometimes a more invasive microscopic approach. The sample is then stored for future use or is used immediately in conjunction with ICSI to fertilise an egg.