Ta filia jest blisko.

Because filia is a feminine noun in Polish, and the demonstrative this must agree with the noun’s gender.

• ta = feminine singular nominative
• ten = masculine singular nominative
• to = neuter singular nominative

So:

• ta filia = this branch
• not ten filia
• not to filia

This kind of agreement is very common in Polish.

It is in the nominative singular.

In Ta filia jest blisko, filia is the subject of the sentence, and subjects are normally in the nominative case.

You can also see that ta matches it in nominative feminine singular:

• ta filia

Filia usually means a branch, affiliate, or branch office of an institution, company, library, bank, school, etc.

So depending on context, it could mean things like:

• a bank branch
• a library branch
• a company branch office

It is a real and correct Polish word, though in some contexts Polish speakers might also use words like oddział or placówka, depending on what kind of branch they mean.

In normal Polish, you usually do use jest in a sentence like this.

• Ta filia jest blisko. = This branch is nearby.

Unlike some languages, standard Polish normally keeps the present-tense form of to be in ordinary sentences of this kind.

Leaving it out:

• Ta filia blisko

would sound incomplete or unnatural in normal standard speech.

Because blisko here is not an adjective. It is being used as an adverb/predicative expression meaning nearby or close.

Compare:

• Ta filia jest blisko. = This branch is nearby.
• bliska would be an adjective form, meaning something like close in a grammatical sense that agrees with a feminine noun, but that is not how this sentence is built.

So in this sentence:

• filia = noun
• jest = is
• blisko = nearby / close

Yes. Very often blisko is used with a noun in the genitive case.

For example:

• blisko domu = near the house
• blisko centrum = near the center
• blisko szkoły = near the school

But when no reference point is stated, blisko can stand on its own and simply mean nearby:

• Ta filia jest blisko. = This branch is nearby.

They are very similar, and in many situations both can be translated as near or nearby.

• Ta filia jest blisko.
• Ta filia jest niedaleko.

Both are natural. Very roughly:

• blisko = close / nearby
• niedaleko = not far / nearby

The difference is usually small in everyday use.

A simple pronunciation guide is:

ta fi-LI-a yest BLIS-ko

A few useful notes:

• filia has stress on the penultimate syllable: fi-LI-a
• jest sounds roughly like yest
• blisko has stress on BLIS

Polish stress is usually on the second-to-last syllable, which is why filia is fi-LI-a.

Yes, Polish word order is more flexible than English, but Ta filia jest blisko is the most neutral and straightforward order.

You might also hear other orders for emphasis, for example:

• Blisko jest ta filia.
• Ta filia blisko jest. — possible, but less neutral

For a learner, the safest default is:

• Ta filia jest blisko.

Yes. That is grammatical and can sound a bit more formal or descriptive.

• Ta filia jest blisko. = This branch is nearby.
• Ta filia znajduje się blisko. = This branch is located nearby.

In everyday conversation, jest blisko is usually simpler and more natural unless you specifically want the idea of is located.