Many changes.

lib/api/controllers/collections/getCollections.ts

@@ -0,0 +1,19 @@
+import type { NextApiRequest, NextApiResponse } from "next";
+import { prisma } from "@/lib/api/db";
+import { Session } from "next-auth";
+
+export default async function handler(
+  req: NextApiRequest,
+  res: NextApiResponse,
+  session: Session
+) {
+  const collections = await prisma.collection.findMany({
+    where: {
+      ownerId: session?.user.id,
+    },
+  });
+
+  return res.status(200).json({
+    response: collections || [],
+  });
+}