Every country has some kind of institution responsible for collecting taxes (perhaps more than one in some countries).
How complicated this is will vary a lot. For example, as /u/sfmclaughlin said, most people in the UK will never have to file a tax return, because income tax (and national insurance) is paid by their employer. I’ve worked for 20-odd years and never had to deal with with HMRC. The US tax code for individuals seems particularly complicated.
On the other hand, the US is unusual among rich economies for having a sales tax rather than value-added tax. VAT is generally considered a “better” tax, but it is considerably more complicated than sales tax. VAT involves tracking the “value added” at each stage of a production chain, but is only actually paid by the final seller. (Though small companies can choose to pay a fixed amount of tax to avoid all this complication.)
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