I don't have any business ideas for you, but your alternative to enter the agro farm is quite good, because now the demand for organic agricultural products and local agro-industry products continues to increase and it can be a good opportunity for you to earn money from there.

while your plan to invest in bitcoin is the right thing. you plan to invest monthly and consistently to do it in the long term with 80-90 dollars is still a reasonable amount to start with, especially you said that if you have the opportunity to get more money, you can invest more money each month. that should be right. it's just you who should be able to adjust it to your financial condition. don't push it too much. you have to prepare emergency money and don't be reckless to sell when the market is bearish.

there's not much I can suggest, your investment plan is right and you should be able to see business opportunities in the area where you live. but my only suggestion is that you need to hold your bitcoin in a non-custodial wallet and take care of it properly. and you need to be consistent with your investment plan. good luck to you.