dar vs regalar
Dar is general giving. Regalar is giving a gift — no payment, no reason beyond kindness or celebration.
regalar
To give as a gift, or to give away for free.
Me regaló un libro por mi cumpleaños.
He gave me a book for my birthday.
Gift. The noun is 'el regalo'.
¿Qué le regalamos a tu madre?
What shall we get your mum as a present?
Regalar is the verb for gift-giving decisions.
Te lo regalo, ya no lo uso.
You can have it, I don't use it any more.
Giving away something for free.
dar
To give in the general sense — handing over, providing, offering.
Dame el libro, por favor.
Give me the book, please.
Handing something over. No gift implied.
Me dio un buen consejo.
He gave me good advice.
Dar for abstract things: advice, permission, time.
Le di las llaves al portero.
I gave the keys to the porter.
Handing items for practical reasons.
Tricky bit
'Te doy un regalo' is fine but clunky; native speakers say 'te regalo X'. And 'dar' for a present can work ('me dio un reloj'), but regalar makes the generosity explicit.