Socialism

Start local. Check the local orgs (DSA, food not bombs, etc) and see if they're doing any real organizing (instead of endless pointless meetings and recruiting at other orgs' protests, like CPUSA). If so, join and see if there are useful ways to resist.

If not, or in addition, form a tenants union, a library of things, a mutual aid, or a group of neighbors to resist ICE. Start a reading group with friends and neighbors.

It will take a mass movement to really combat capitalism. The skills of mutual aid and solidarity will be absolutely key.

Welcome! Becoming aware of the problem and seeking a solution is the first step, so you're already on step 2! The shortest, most oversimplified answer, is organizing the working class and overthrowing the Capitalist system, replacing it with a worker-run system. So, joining an org, like a Socialist party, is the answer.

But why is this method correct? How can we best organize? What conditions are getting in the way of that, where is the world turning? How did we get here, and where are we going? All of these questions are going to be better able to be answered with reading theory. I made a "Read Theory, Darn it!" introductory Marxist-Leninist reading list, designed to take you from no knowledge to a firm, grounded understanding of Marxism-Leninism, as quickly as possible. I recommend checking it out!

Feel free to ask any questions, comrade!

Well I could link you What is to be Done by Lenin and leave it at that but while much of it holds up to this day we have learned much since it was written. You should absolutely still read it but I would understand not doing so. Ultimately the best form of resistance is collective. Look for leftist organizations near you, join them and honestly engage with them. Personally I am partial to PSL but it is not everywhere. If there aren't left wing orgs with a major presence near you then join other forms of community action like soup kitchens or community gardens. If your work doesn't have a Union try and make one if you feel safe enough to do so, the IWW can help with this if you are inexperienced. If none of this is possible then atleast meet your neighbors, find likeminded people in your area and talk about your political passions, maybe something can come of that.

Join a serious communist party that isnt defending indentitarian politics

Let's just say that voting and strongly worded tweets never worked.

Every socialist country had a revolution.

Welcome!

First thing I'd recommend: we are clearly not the first people to ask that question. There have been generations of radicals who spent their lives combatting capitalism with different strategies and tactics. Some of them were kind enough to write them down, the least we can do is pay them back by reading what they had to say with an open (but critical) mind.

I'd recommend starting with Socialism: Utopian and Scientifi. There were many socialists in the 19th century with various theories about how they could triumph over capitalism. Some thought it would come easily, they naturally just had to appeal to workers' interests and the workers would take it from there. They were wrong (see: Paris Commune). The movement away from capitalism is an enormous task and it requires us to be fully aware of its scale if we are serious about accomplishing it. Marx and Engels are widely acknowledged to be the thinkers who properly assessed the enormity of the task, and whose theories have proven most useful for those who wanted systemic change.

As to what I think you should do in the real world: join an organization. Anything is (probably) better than nothing. The US has the PSL, other countries have lots of different movements and parties. If your org is more concerned with infighting than mutual aid, you're better off going to something else (hell, you might get farther in helping people with a church than a sectarian org).

Recently found this may be helpful. I am still not sure about the quality of the info because I haven't read much from there, but there seems to be sections on organizing and marxism 101 that may help you.