Show linear bounded automata accepting w is PSPACE-complete ALBA={⟨M;w⟩ | M is linear bounded automata which accepts input w}

Show that ALBA is PSPACE-complete.
How I would try to solve it...

We need to prove ALBA belongs to PSPACE. So I would construct TM A which accepts &lt;M;w&gt;. Simulate M till qng^n steps or when it halts. If it halts: Accept &lt;M,w&gt; if M accepts w, otherwise reject.
How would be space complexity? I would say it will need n (=size of the tape) so space complexity should be O(n) and then ALBA belongs to PSPACE. Is it correct?

We need to do reduction from TQBH to ALBA to prove that ALBA is NP hard, but I have no idea how to do it. How should this reduction be done? TQBF must be 1 if ALBA accepts w i guess, but dont know how to show the proof...
Savitch's theorem shows that PSPACE=NPSPACE, which immediately implies that ALBA is in PSPACE.
In the other direction, suppose that $L$ is a language in PSPACE. Thus $L$ is accepted by some machine that uses space $p(n)$. We can construct another machine $L'$ which accepts an input $(x,y)$, erases $y$, and simulates $L$ on $x$. We can reduce $L$ to ALBA by mapping $L$ to $L'$ and $x$ to $(x,0^{p(|x|)})$.