Disclaimer new to bitcoin: Do I need to make a transaction with an existing account before receiving first time payments to legitimate verify my account ?
All you need to receive funds is a valid bitcoin address. To create a bitcoin address, users will generally use some software that is capable of creating the cryptographic keys that the bitcoin address is derived from.
So, in the most simple terms, all you need to do is download some Bitcoin wallet software, which will then provide you with a bitcoin address you can receive funds to. All you need to do, is copy that address and send it to the person who wants to pay you.
Note that for every payment, you should send a new receiving address (any good wallet will give you a new address automatically each time a payment is received. This is very important for your privacy (and the privacy of those you transact with).
Do I need to make a transaction with an existing account before receiving first time payments to legitimate verify my account?
Correct me if I'm wrong, but it seems like you are asking if you need to spend from your wallet in order to verify that you are the owner of a payment address. The answer to that question is no, you don't need to spend first. If you want to prove to another person that you own an address, you can sign a random message string using that payment address. Then another user can verify the signature of that message, which lets them know that you are the owner of that address.
I believe most wallets include this feature, but for example, here's how you would accomplish this using Electrum with the console:
>> message = "this is a random message" >> address = getunusedaddress() >> address 'bc1q2zyqwnur9fslzwvhntyqpg9zp5nlaffczed95n' >> signature=signmessage(address,message) >> signature 'H1gN7O4SGoeNrRbf4RuznMDrTqHM3sRfzNM2h7qfPjBTPKE/6/UJ+ktOM80PgJ3dvId/xAK7n94F4imSEnqnafA=' >> verifymessage(address, signature, message) true