How to enable mining on daemon? I forked bitocin and created a altcoin.

Now I am running a node of it. There are currently 0 blocks because there are no miners. How can I enable mining on bitcoind?

I tried adding gen=1 with config, but it's not mining.

I believe there was a setgenerate true command, but I am not sure how to use it. How can I make my node mine coins?
I believe you can still use the generate and generatetoaddress commands to mine a certain number of blocks. setgenerate was removed in version 0.13 because mining with bitcoin core on mainnet is useless and has been for a number of years:
https://github.com/bitcoin/bitcoin/blob/master/doc/release-notes/release-notes-0.13.0.md#removal-of-internal-miner