Trying to make my own modpack for the first time. I need some help.

I'm making a modpack for 1.20.1 with TFC, Mekanism, Thermal Expansion, Railcraft and a couple of other mods.

My first problem is that I haven't been able to make all the mods compatible. For railcraft there was a mod specifically for raincraft and TFC compatability, but I've found no such mod for TE and Mekanism. I used to play TechNodeFirmacraft, in which osmium used to spawn like other TFC ores and you could use wrought iron in place of vanilla iron for other mod's recipes. I can't figure out how to make my modpack do either of these things.

Secondly TFC itself seems to be missing some features it once had. Skills and temperature indicators are gone. Is there any mod that adds these back?