Li, you don’t mention whether you using this on Windows, Mac or Linux, however, from the SDRplay website you can also download other SDR software such as HDSDR (Windows) and CubicSDR (Mac, Linux):https://www.sdrplay.com/downloads/
SDR# (SDRsharp) will also work but you will need to install the Extio DLL appropriate to the RSP1A, which can also be downloaded from the above page. The version of HDSDR on Windows from SDRplay already comes with the necessary drivers for the RSP devices.
Bear in mind that these other programs do not have the scanner feature, so if that is of interest then you will need to stick with SDRuno.
As for the scanning itself, if you want to scan the FM broadcast band and create a bank (i.e. everything from 88.000MHz to 108.000MHz) use the ‘Range’ option and in the Scanner Config panel. Click SCANNER CONFIG and select a custom preset from the dropdown. Give the preset a name. Set up the frequency range. Entry is in hertz, so you will need to put 88000000 for the Start Freq and 108000000 for the Stop Freq. For the FM broadcast band, the frequency step will be 100000 (100kHz) and make sure that the ‘SAVE TO MEM PANEL’ option is checked. To search for stations, you will probably want to set a short short hold time (1 or two seconds) and uncheck ‘WAIT ON SIGNAL?’. Set the threshold just above the background noise level you see on the waterfall. Click ‘Save Preset’ to save the settings.
Also, before you start the scan, make sure that the receiver is set to FM modulation, WFM mode and a filter width of 192000. Set the squelch level to the point where it just blanks out the background noise level on the band (not on a station) so that you get silence. Once the range, receiver mode and squelch have been set, you can then start the scan. The scan will not run while there is noise or anything audible coming through the speaker/headphone. Any active frequencies where the scanner finds a station should be automatically added to the bank.
Page 31 onwards of the user manual is quite helpful:https://www.sdrplay.com/docs/SDRplay_SD ... Manual.pdf
While the scan is running you should hear short clips of stations and frequencies added to the bank. After is has been running a while and the list of frequencies is no longer growing, you can stop the scan. When you click on a frequency in the bank, you should be able to listen to that station. Now save the bank!
I recently set up a bank for airband in a similar manner and it works OK, but obviously using the frequencies for airband (118000000 - 137000000). I used a 500hz step size, but it is possible to use 1kHz or 8.33kHz as well. The radio would, of course, need to be set to AM modulation. Once frequencies have been searched and added to the bank, to listen on airband you will probably use the MEM scanning option so that is scans just the frequencies already added to the bank rather than the whole band, and check the WAIT ON SIGNAL? option so that every time the scanner finds a signal it will pause while the signal is present to let you listen and it then waits a few seconds for a response before moving on o the next signal.
SDRuno is actually a very good SDR program and while the scanner dows have limitations it does work quite nicely. Stick with it. You will get there eventually, just take one step at a time.