Which is best motor swap i can put into my 1998 honda civic hx?

Car currently has no motor and i want my car to be fast

Because it's a front drive platform, you're pretty much limited by what engine the factory put into that model. Anything other then that is going to be complex & expensive.

There are a few I can think of out of thin air: B18B1: Just bolt in. B18C1 / B16A2 / B18C5 / B16B / D16Y8: Bolt in with the VTEC controller will need to wired in. The H22A: The VTEC controller will need to wired in, and Hasport shift linkage will need to be used.

To make it short: Read the article in this link:
http://www.modified.com/tech/0407scc_k_series_engine_ek_civic/

Need your budget.

No way of helping you without knowing how much you are willing to blow on it.

On top of that, do you have your own engine hoist? Tools, shop, electrical/wiring experience? Or are you having a shop do I it?

Do you have a transmission?

How much power are you expecting?