| Getting the best sound from that amp will be challenging. I'd guess it has 4 knobs; Bass, Mid, Treble, Volume. The louder you go the worse it will sound, but you'll need to be able to hear what you are doing. Try the tones all at halfway, then vary them one by one; try Bass at 0 then 2.5 then 5 then 7.5 then 10 then back to 5 & do the same thing for Mid & then for Treble.
The bass likely has 2 knobs; Volume & Tone. "Neutral" for Tone is full clockwise, & it will cut treble & some mids as you turn it counter-clockwise. I'd set your amp Tones first then work the bass Tone, then perhaps revisit the amp Tones for fine tuning.
A trip to that store will be well worth the drive. Bring your bass. New strings & a tuner might be in order (I suggest a tuner with a metronome built in).
Your bass is likely OK, but that's guessing. Trying it at the shop will let you know. There's better than old Squier, but that's a fine bass for beginner & for a few levels above.
I think you'll want another amp. A small practice amp will do you for awhile.
You might find some good tips in the General Instruction forum here. | 
