Quote from: magenson on Today at 02:37:27 PM

Yes, maybe WordPress site with Force Login plugin which asks on log-in first in order to view site will do the job, because i just need simple site with log-in before access, not either payment system or so, but..

I can just install WP Plugins if buy Bussiness which costs 299$ per year. That's bad. Is there any free alternative to that?

It's really hard to find good and free WP plugins with many functions. Usually, you can find free but very limited plugins while for an additional fee, you can get additional options.
For example, probably default membership plugins (Yes, proper name what you need is "membership") is wp-member https://wordpress.org/plugins/wp-members/#description here you have something for free, but from $59 per year, you will get more options. Much cheaper than $299
Next is one of the most used membership plugins: https://www.paidmembershipspro.com/pricing/ there you also had a free plan with almost all of addons and functionalities. Payments gateways etc...
I will give you another one suggestion https://s2member.com/ where you also have a free version, although this is the most favourable for the purchase. $89 Lifetime licence for one website or $189 lifetime for an unlimited number of the websites.

As you can see, there are many options and all of them you can try for free. I suggest you first to try it all then make a decision based on which one suits you best. Watch it as a tool to make money, a good tool cannot be expensive.