you could try building one of thesehttps://www.instructables.com/id/Desulfator_for_12V_Car_Batteries_in_an_Altoids_Ti/
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Either the battery is junk, the alternator is junk (and not charging the battery), or you left an accessory on (headlights, seat heater, etc).
Get your battery checked at a local shop - they can test it and tell you if it needs replacement. Same with alternators (if you're comfortable taking it out).
The connection to the battery could be corroded and need cleaning.
Depending on the battery, it may need more water added.
If the alternator belt is loose, it might not be charging the battery.
None of these make the components 'junk', they are just maintenance.