I’ve learned 4 songs in a week😃

So I bought my first bass about 3 months ago in order to perform in my schools talent show and the only experience I had with a bass was playing two notes for like 5 mins, however I’ve known how to read guitar music because of acoustic guitar. For the talent show I really wanted to play a SpongeBob song, brain stew by Green Day, and two blink-182 songs —all the small things and I miss you—. I started ACTUALLY practicing about a week and a half ago and I was able to learn them all in about a day I’m so happy with my progress. But one thing that idk if is too bad is that I been using a pick and my tio who’s a guitarist was saying that you’re not supposed to use a pick but I play fast songs so I kinda needed it. Anyways I learned all four songs and for the SpongeBob song (surprisingly the hardest to learn) it took me about two hours to learn it, now I’m just cleaning them all up and I’m tryna learn how to sing along with play. Also does anyone have tips for chords and how to not get that buzzing sound⁉️ also how does everyone feel about putting stickers on your bass..