Can you use a secured credit card to check into a hotel. Not to pay, but when they ask to put a card on file.?

Yes. A secured cc is a real cc, and no one but you knows it is secured.

It would depend on the amount of the hold. For example, prior to using a credit or debit card at the pump, they do a $50-99 authorization. If it fails, you can't get gas. (without going inside and specifically buying $15 or whatever)  

If the hotel test charges more than your availability, its not going to work.

Im guessing a $300-500 limit might not be enough. For damages and or if you stay a week.

I rented a hotel when I was young but I do not recall my exact credit limits. Probably several thousand at the time at least.

Only if there's enough money on it.

They put a "hold" on an amount of money that will cover your entire bill including extras like room service. The money is still in your account but you can't spend it on anything else until the hotel releases it. If your card can't handle a charge that size, it will be rejected.