There are several different notions of infinity.
Infinity as a limit describes what happens to a function, and simply describes some variable getting larger and larger as some other variable does something.
Infinity as a quantity (known as cardinality) is a different notion of infinity. But, there are different sizes of such infinite quantities. The smallest such infinity is that of the 'number' of counting numbers (positive integers). The 'number' of decimal numbers is a larger infinity than this.
There are also ordinal concepts of infinity. Such can have either infinite ascent, infinite descent, or both.
Of course, this is about debates. But -- for me -- it's hard to debate the following: Thoughts are appreciated, though.
"Does Infinity have a beginning? It really just depends on the infinity you describe, whether it will have a beginning or not. Most infinities do have beginnings, simply because in order to tangibly grasp the concept of whatever infinity we are talking about (just based on the limitations of the human mind) we generally need a starting point."
What Is The Largest Number Before Infinity? - The Biggest (the-biggest.net)
There is no 'largest number', and no 'largest number before infinity'. And infinite sets need not have a 'start' nor an 'end'.
If Infinity is a quantity, then are the following mathematically correct or just meaningless?
Infinity + Infinity = Infinity
Infinity x Infinity = Infinity
Infinity^Infinity = Infinity
Infinity is more of an abstract idea than an actual quantity.
What happens here depends on the type of infinity. For limits, these equations are all correct.
For cardinals, a sum or product of infinite cardinals is the larger of the two. Exponentiation is a lot trickier. If you want an exposition, I will be happy to give one after I'm back from vacation.
For ordinal infinities, things get stranger.
Infinity has neither a beginning nor an end. That’s the whole point, surely? A thing without limits has no boundaries
And if it exists at all, it can only exist beyond time and space.
Boundaries are a concept from geometry (or topology). Most versions of infinity are not in that context, so the notion simply doesn't apply.
Infinite in extent is different than having no boundary. For example, the surface of a sphere has no boundary, but is finite.