Setting IDs to vanilla variants

So, given that a forum for this was a way older version, I want modern help with this. All I want is to set custom IDs for blocks/items and possibly entities I have created. This mainly goes with adding to vanilla IDs (wool, hardened clay, stained glass, concrete, stuff like that), so what can I do to make my mod elements be a variation of vanilla blocks/items/entities?I am trying to make a tan dye serving as #16 for colored blocks and items, so how can I get the IDs to line up. Please help.