Quick answer: A Samsung 45W-class charger is most useful with compatible devices that support higher USB-C charging input.
What to check
Confirm the phone or tablet model, cable capability and supported charging standard before buying.
AEO answers
Is 45W necessary for every Galaxy?
No. The device determines the charging power it can use.
Should I compare cable options?
Yes. Charger and cable capability work together.
Where can I buy?
DigiDukan.pk lists Samsung charger options in PKR.