If a mans semen is clear does it me he's infertile?

Semen: No, it does not mean he is infertile. Only examination under microscope will tell the number of sperm and their quality, size, shape, deformities etc.

No: You can not determine if a man is infertile by just looking at the semen. To test for male factor infertility you need a full semen analysis where the ejaculate is examined under a microscope by a trained technician who counts the number of sperm and examines their shape and motility.