Conditional questions

I think what you're after is conditional form fields, and both parts are doable.

For each question, click the field in the form editor and turn on “Show field only when conditions are met," then build a rule against your channel multi-select:

• Paid Social questions: show when Preferred channel "has any of" Paid Social
• The other set: show when Preferred channel "has any of" Organic Social, Employee Advocacy, Executive Advocacy

"Has any of" lets you cover all three values in a single rule.

To hide everything until a channel is picked, just add a condition to every downstream question. A multi-select starts empty, so any condition referencing it is unmet until the respondent chooses something, which means the questions stay hidden automatically. Only the channel picker shows at the top.

A few things:

1. Conditional form logic is a paid-plan feature (Team plan and above), so it won't appear on the free plan.
2. The channel field has to sit above the conditional questions in the form. Conditions can only reference fields that come earlier.
3. Because it's multi-select, picking both Paid Social and Organic Social will surface both question sets. If the paths should be mutually exclusive, then use a single select.