It takes too long to do a transaction. people get impatient when the card reader takes more than 10-20 seconds, do you really expect them to wait 10 minutes to buy a candy bar.
I don't. I know I wouldn't. But I also don't consider bitcoin to be the perfect asset for small transactions, such as buying a candy bar or a lollipop. When it comes to bigger deals, especially where money goes across international borders that would require currency conversions and international bank fees if you are using traditional systems, bitcoin performs quite well.
I don't mean fear as an investment, I mean simply losing the numbers or sending them the wrong place or losing the "wallet" or hacking.
Those are the risks you have to bear with to become financially independent and make decisions when you want to and how you want to.
I managed to buy bitcoin on coinbase and make a transfer to bittrex following step by step (x about 30 steps) intSructions on youtube.
The process of sending/receiving bitcoin isn't that difficult. Exchanges guide you throughout the process. it's as simple as inserting your wallet address, confirming your transaction via 2FA (if activated) maybe an additional confirmation via SMS/email, and that is it.
Now I think I am supposed to have a wallet (or maybe not I read some places) but why does coinbase have "wallet" in the name?
You can keep the coins you purchase in the online wallets of the exchanges. But this is not recommended for various reasons. It's not your coins, it belongs to the exchange. They become yours when you transfer them to a wallet whose private keys you control. You are also relying on an exchange to keep your coins safe and that is not how bitcoin should be used. You should be the one who safeguards the assets, and only you.
I think I am supposed to have a private address and a public address but which numbers are they?
Your public address is used to receive bitcoin. If you need someone to send you coins, you need to give that person your receiving address. The addresses are the strings that start either with a '1', '3', or 'bc1'. The private key is what gives you access and unlocks the coins located on those addresses. It is that long string (from 51-64 characters) of letters and numbers. You will most probably see them beginning with '5', 'K', or 'L' depending on if they are compressed or uncompressed, but don't bother yourself with the terms for now.
Then there are places to put just "address" --which one? or is this a 3rd address consisting of a combination of the other 2?
Your public address, always your public address. Your private key is called 'private' for a reason. Only you should have it and know where to find it. Whoever has it, can empty the public address it is associated with.
I think I am supposed to have a private key. Is that one of the numbers? That is what I read on google.
I mentioned that above. It is that long string of characters that has to be kept safe and remain private.
They gave me 12 word code. Is that my "secret" key? Hardly a secret since I had to rearrange the words in order to send the bitcoin to bittrex so obviously coinbase has it.
Those 12 words are called a seed, seed phrase, mnemonic phrase, recovery seed, and there are probably some other names for it. That is the most important part of your wallet. All your public and private keys are generated and restored from that seed. One private key gives you access to the funds located on one public key. You can lose these private keys but still restore your coins thanks to the seed phrase. But it doesn't work the other way around. If you lose your seed, and have only one private key, you can only gain access to the one public address that key corresponds to.
I am not sure what you meant when you said you had to rearrange your seed before sending your coins to another exchange. Care to elaborate on that? That is not how it works and you don't need the seed for sending/receiving. It should never by inserted online or saved digitally. You should write it down on a paper and keep it somewhere safe. If you have already entered it somewhere, consider it compromised. I would suggest you move your funds to properly created wallet.