Conditiional sentences always bugging and ruining my game can you help me figure out whats wrong?

You’re using the assignment operator in a conditional statement, which essentially confuses the logical operation, it’s understanding "assign he variable No to 4". There is a large difference between the assignment and comparison operands within coding languages, and this needs to be understood quickly as you can cause a lot of semantic errors, as seen above.

The operator you need to use is ==. This doesn’t solve your problem however, you cannot recursively call or in this scenario without properly providing another comparison expression, this is what’s causing the conditional to pass regardless of the malformed statement.

On a positive note, you can concur if a number is a multiple of a factor by using the modulo operator %, which retrieves the remainder of a division; in the case of x being a factor of y would be 0. This will allow us to run a single condition, without needing to compensate for range.

local Number = Random.new(tick()):NextInteger(1,20)

local Factor1 = 4
local Factor2 = 5

if ((Number%Factor1) == 0) then
    print(Number.." Is a factor of "..Factor1)
elseif ((Number%Factor2) == 0) then
    print(Number.." Is a factor of "..Factor2)
else
    print(Number.." isn’t a factor of "..Factor1.." or "..Factor2)
end

Note:

if calls a conditional scope. elseif provides an alternative condition. else concludes all conditions aren’t met.

If you’re wondering what Random.new() is, this is a more dirverse form of math.random. It returns a Random Object that can be initiated with a seed, which allows us to build a more randomized pseudo-random number. It contains many methods allowing us to be versatile on our return calculation as well. TL;DR: More efficient and versatile.