Here are the corrections for each sentence:

1. **Correction:** We don’t want **to buy** any writing pads?
- **Error:** "buy" should be "to buy."

2. **Correction:** They have lived here **for** 5 years.
- **Error:** "ago" should be removed; "for" is the correct preposition for duration.

3. **Correction:** Mr. Long doesn’t like **drinking** green tea and I don’t like, too.
- **Error:** "drinking" should be removed or "to drink" should be used. "like, too" should be "like it, too."

4. **Correction:** I like bananas, or my brother doesn’t.
- **Error:** "or" should be "but" for correct contrast between the two clauses.

5. **Correction:** Lan will have **a small** party for her next birthday.
- **Error:** "has" should be "have" and "a small" provides clarification; however, if you meant to keep "has," it should be restructured as "Lan has a small party..."

Overall, the sentences need adjustments for correctness in grammar and typical usage.