To successfully become a Bitcoin miner

To successfully become a Bitcoin miner,

you have several options. You can use your existing personal computer to use mining software compatible with Bitcoin and join a mining pool. Mining pools are groups of miners that combine their computational power to compete with the large ASIC mining farms.
If you have the financial means, you could also purchase an ASIC miner. You can generally find a new one for around $20,000, but used ones are also sold by miners as they upgrade their systems. There are some significant costs such as electricity and cooling to consider if you purchase one or more ASICs.