How to get money when using regtest
Just generate some blocks.

bitcoin-cli -regtest generate 101


You will have them in your wallet and can use the funds once confirmed. 101 is the number of blocks to create.
You can use any integer that's at least 101 as the number of blocks.
You cannot use a smaller integer than 101 if you want to test transactions, because of the 100 block maturation time.