What Are Good APIs (or reference guides) For "Number Reference"?

Hello SH,

Does anybody know a good reference or an API for Number Resolution? This is for a 'Touched' event, for when you step on the part, the baseplate "turns" into terrain (script is below).

part.Touched:Connect(function(hit)
    if hit and hit.Parent and hit.Parent:FindFirstChild("Humanoid") then
    game.Workspace.Terrain:FillRegion(CFrame(0, -10, 0), *number resolution*, "Leafy Grass")
    Baseplate.Visible = false

Terrain needs to fill entire baseplate, in which orientation is set to 0, 0 ,0.

If anybody knows any good references or APIs on number resolutions, please DM me via Discord (user is RealMathGeek#6390) or reply to this post. Help is VERY much appreciated at this point!

-RealMathGeek