How do you drink alcohol for the first time?

28 year old man wanting to drink for the first time. I can't handle reality and drinking seems to be the most socially acceptable.

1: How do you know what is your limit to not be affected in a bad way?

2: Is cheap beer worse?

3: Is damage to your liver based on a random chance each time you drink, or is it based on the total amount you drink over time?

I do not have a license and will not be driving. I do not have a family and won't have children. So won't be harming others.

Thank you.

EDIT: Already gone to therapy. Also, I'm not going to kill myself. But I need something to dull reality until I die of old age. So please stop mentioning therapy at least