maybe one knows if is done in the audacity to use Lo-fi ??

What is your question?

Can i use LO-FI technical on audacity…??

What is “LO-FI technical”? Is it a plug-in of some sort, or another program, or what?
Have you tried using it? Did it work?

Here is from https://en.wikipedia.org/wiki/Low_fidelity:

Low fidelity or lo fi (adjectival form “low-fidelity” or “lo-fi”) is a type of sound recording which contains technical flaws that make the recording sound different compared with the live sound being recorded, such as distortion, hum, background noise, or limited frequency response. The term “low-fidelity” is used in contrast to the audiophile term high fidelity or “hi-fi”, which refers to stereo equipment that very accurately reproduces music without harmonic distortion or unwanted frequency emphasis or resonance. The ideas of lo-fi are taken to extremes by the genre or “scene” of no fidelity, or no-fi. Some lower-budget recordings from the 1970s and 1980s have a “lo-fi” sound because of the limitations of the analog recording and processing techniques of the time, which introduced unwanted artifacts such as distortion and phase problems. In some recordings, however, high fidelity recording is purposely avoided, or the artifacts such as simulated vinyl record crackles are deliberately retained or added in for aesthetic or historical reasons.

Some unique aural qualities are available only with “low-tech” recording methods, such as recording on tape decks, or using analog sound processors (e.g., analog compressors or reverb units). The lo-fi aesthetic has even contributed to musical subgenres, such as the “lo-fi” subgenre of indie rock and a great deal of punk rock.[1] Lo-fi techniques are espoused by some genres outside the indie rock world, particularly by certain heavy metal bands (especially within the sludge and black metal scenes), where the very low-quality of the recording has become a desirable quality, as it is associated with authenticity, as well as a “darker” sound or a “rebellion” against good production.

In digital audio, the term “lo-fi” usually refers to an audio file with a lower bit rate or sampling rate, and thus a lower sound quality. Such audio files may be offered on the internet because of their smaller file sizes and hence shorter download times. The term “lo-fi” has come to be used figuratively in other contexts, by analogy with lo-fi audio, usually to mean “low-tech”, such as websites with very simple architecture or designed for users with low bandwidth connections.

In some recordings, high fidelity recording is avoided, or the artifacts are deliberately retained or added to all or part of the recording for artistic reasons. This decision is usually made by the record producer, but in some cases, band members are advocates of the “lo-fi” sound.

There are LOTS of ways to lower the quality (fidelity) of a recording…

The main categories of sound qualty are noise, distortion, and frequency response.

  • You can use the Generate tool to generate noise, which you can later mix with your audio. Or, you can record some noise of your choosing and mix it in. You can mix-in a tiny bit of noise, or s ship-load of noise.

  • To create distortion (clipping), you can boost the volume so that the peaks are above 0dB, then save (export) as a regular 16-bit WAV file. The more you boost, the more distortion you’ll get.

  • You can alter frequency response with the Equalizer Effect. You can make barely noticable changes or drastic changes.
    i.e. Cutting frequencies below 300Hz and above 3000Hz can give you a telephone-like sound.

  • Encoding to low bitrate MP3 (I think 32kbps is the minimum) should give you some compresion artifacts.

  • Saving as (exporting to) 8-bit WAV will also degrade the sound quality.

  • Recording with the microphone built into a laptop (or any regular-cheap “computer microphone” will give you low quality.

  • If you can find a portable cassette recorder, that should give you low quality.

  • There is a free plug-in called [u]Izotope Vinyl[/u] that simulates the sound of a vinyl record, but I haven’t tried it and I don’t know if it works with Audacity.

  • You can also find plug-ins to simulate analog tape or tube amplifiers.