Black and red bugs in enclosure
These are weevils. They are plant-feeding insects and should not have any impact on your igaunas.
Two possibilities may explain why you found this weevil:
1) If you recently purchased the iguana, the weevils could have been stowaways in the packing material.
2) The weevil could have arrived in the food being given to the iguana. I can't identify the species from the photo, but this one https://www.canr.msu.edu/resources/grain-weevils is one that sometimes appears in households.