My question is I never really sold crypto or anything last year and my mother in law filed me, my fiancee and my son as dependents. Do I still need to file?

As a dependent, your filing requirement is $1,100 for unearned income, which is how income from investment is categorized. If you made more than that amount in crypto sales, you will need to file. You may have also had earned income or self-employment income.

Tax filing requirement (for dependents)

The minimum income requiring a dependent to file a federal tax return. 2020 filing requirements for dependents under 65: Earned income of at least $12,400, unearned income (like from investments or trusts) of at least $1,100, or self-employment income over $400.

If I send you the amounts I earned can you help me to determine whether I need to file my Cryptocurrency?

If you made more than $1,100 with your cryptocurrency or other unearned income, like unemployment, then you will need to file a tax return this year.  You can file a return at no charge for federal or state at TurboTax FreeFile.  If you are the dependent of another person, be sure to put that on your tax return.