It actually depends on how much capital you are willing to raise and risk at the same time without hampering your financial condition.
You can utilize the search bar in the forum to look for various threads and posts about earning bitcoins as this question has been raised several times already.

Now as a beginner, it is essential that you should know what you are investing. Manage your free time by reading books, watching videos, and learning through this forum about anything relevant to cryptocurrencies (or bitcoin to be specific) so you could grasp a quick background on how the market works.