RichText coloring with variables?

Your mistake is in the quotes, you can use double quotes(") and single (') to separate the strings, try this

word.Text = "<font color='#00BE00'>"..Variable1.."</font><font color='#FF0000'>"..Variable2.."</font>"

if you only will use rich text for color, you can make a function to make it easyer

local function toRichText(...)
	local args = {...}
	local texts = {}
	for i,v in next, args do
		local colors ={v[2].R, v[2].G, v[2].B}
		texts[i] = "<font color='rgb("..table.concat(colors, ', ')..")'>"..v[1].."</font>"
	end
	return table.concat(texts, '')
end

-- Single text example:
word.Text = toRichText({'Hello', Color3.new(0, 170, 255)})

-- Multi text example
word.Text = toRichText(
     {'Hello', Color3.new(0, 170, 255)}, 
     {', how are you?', Color3.new(0,0,0,0)}
)