Thanks for the answer, at least 1 answer to that post lol, I was waiting desperately that some Legendary gurus come to help, but no luck!
Actually, Bitcoin Core 0.17.0.1 (latest at the time I am writing) has a lot of security checks, that are basically blocking any altcoin to be developed from their source code without removing them.
I understand that Bitcoin needs to be secured, but adding a "if (nheight>somevalue) {" when they are adding these security checks would help newbies to get into this code in a shorter time.
Some would say, if you cannot find out, then you are not good enough to maintain a coin, I got these kind of answers from people who are supposed to have a hi-IQ in these forums. Amazing.
So now the way to overcome the fact that there is no internal mining code (since version 0.14) is to use a pool and stratum.
I have fixed my problem by installing Yiimp (there are install scripts for each version of Ubuntu, latest is here:
https://github.com/xavatar/yiimp_install_scrypt_ubuntu18.04 )
Once you have installed Yiimp, you can use ccminer to premine or just run the blockchain because without mining the blockchain is dead.
You need to comment all the timing/headers/Tips security tests otherwise your nodes will ban your mining wallet, or just comment the ban system as it is not working for new coins...and that's it.
No documentation about these kind of issues in any "make your own altcoin in 10 min" posts of course. All these tutorials are deprecated for Bitcoin 0.17.x