i have a pack of guitar strings that was given to me for a les paul but i need strings for my fender,

so do all guitar strings fit in any guitar?
Well, electric strings will fit most electrics. But some string gauges work better with different instruments. For example, you'd generally want light strings on a superstrat to improve noodling, in the same way that you'd want heavy strings on an archtop to improve jazz tone.

What gauge are the strings. If they're a 9-42 or a 10-46, or even an 11-48, they'll be fine for either.
well they must be electric guitar strings, if they are, then yes

Epiphone Les Paul Standard Plus-Top, SH-2 and SH-5
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Baron Acoustic
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Roland Cube 15
Dunlop Crybaby From Hell
Dunlop GCB-95 Crybaby
Boss MT-2 Metal Zone
Boss PH-3 Phase Shifter
Boss BF-3 Flanger