Hi,
currently, the mining reward is 12,5 BTC for each block mined.
But that won't be always the case. In approximatively 685 days, Bitcoin block reward will be halved, which means miners will only be rewarded with 6,25 BTC afterwards.
Reward is halved every 210,000 blocks.

If you want to know more about reward halving, you can go there:
https://www.bitcoinblockhalf.com/
and here:
https://blockonomi.com/bitcoin-halving/