Can I restore a Litecoin wallet with Public / Secret? I apogolize if this has been asked, I have spent several hours trying to figure this out.

I found an old document of my with a Litecoin Public and Secret key.


I don't have a *.dat file, is this a problem?
I do have The Public key is 34 characters
I do have The Private key is 51 characters
I am using Litecoin Core Qt - Wallet (Which I used in 2015).
The blockchain is downloaded (About 10GB), yet it just sits here
Q1: Do all I supply is my private key?
Q2: Is there a way to check balance with any of my keys, or conversions below?
Q3: Are coins lost if you don't have the .dat file anymore?




In the Application, I can run the Debug &gt; Console and run:

# (This is a fake address, but it's in this format)
importprivkey "6vpo4RFWLcGhk4VsdFk34K3243K3kdsk4k23k32kAkasdkewkwe" "Jesse"`


The above gives me a "Receivable" key under Receiving Address which is identical to my Public key (34 characters).

I used some Online Bitcoin tools to convert the Public key, I thought I might need to run importpubkey, key it's must be there since it's visible in my Receiving Address? 


I'm not sure what for but I was able to get:
(a) (Address to Hash): 40 character hash
(b) (Hash to 160 Address Bitcoin, using a): 34 characters
(c) (Pubkey to Hash, using a): 40 characters


I'm not sure what all this means, this is terribly confusing I don't remember how I did this in the past. If anyone could give me a plain answer I'd really appreciate it and I'll be sure to tick it off as correct and settle the issue :)
All you need to do is importprivkey. The software will handle everything else. Everything else it needs can be derived from the private key, and it will do so when you give it a private key.