In vanilla, you can find steel as ore and you can mine it.
Some mods change that or add stuff.

Expanded Material - Metals in the 3.x list version is adding great metal recipes and stuff, changing rimworld to a bit dwarf fortress... but it does not fit 100% the collection. Because there is so much to do, the more complexity here can harm you. MY Opinion.

For 4.x i removed the complex metal chains but only added coal + iron = steel.
Every other metal from metal+ mod can be mined but will not change recipes.

Expanded Material - Metals really patched stuff. Conduits are build with copper. Geothermals need concrete... and so on.

The default is now:

Coal Expanded (adds coal)
Vanilla Iron and Steel (no steel to mine, steel is smelted out of iron)
Metal+ (added copper, tin and such but do not alter recipes)
[WD] Simple Concrete (adds concrete)

IF you want the complex chain,exchange Metal+ by Expanded Material - Metals, also remove simple concrete and vanilla iron + steel.

IF you want go complete vanilla, remove metal+ and iron + steel mod, Perhaps coal too if you want go full rimfeller.

I would stay with concrete mod.