A male with no obvious nutritional causes for low iron needs to have it investigated. My low iron is very clear as weight loss made my cycle go a bit nutso and I now get to periodically bleed for multiple weeks at a time.
I've tried a bunch of forms but now I'm on Ritual Iron Bisglycinate taken every other day. I thought their "pretty" pills were a gimmick but my lab results show they do indeed work better than even other bisglycinate pills. Much higher cost

. There's many people making a big deal about needing heme iron out there but I'm getting the best results from these non-heme ones.
I take them every other day first thing in the morning on an empty stomach and then give it at least another hour before I eat anything. There are just so many things that interfere with absorption I don't want to bother with it. I take vitamin C or a vitamin C food with my meals. You can have some pretty strong iron absorption blocking factors on board and vitamin C makes it a non-problem.
I'm at the point where I get very irritated with doctors consistently prescribing the hardest to stomach, lowest absorption forms of iron taken in the least effective way. Anemia and iron deficiency is very common. There is no reason they should be so incompetent at treating it.