No, Kaṣāyapāhuḍa (Kashayapahuda) does NOT contain all 14 Purvas.

• According to Digambar tradition, all 14 Purvas and the whole Dṛṣṭivāda (12th Aṅga) are lost.
• What we have now in Kaṣāyapāhuḍa and Ṣaṭkhaṇḍāgama are understood as:

- texts based on portions of the old Purvas (especially karma and kaṣāya doctrine), - not the complete original Purvas themselves.

So:

• Kaṣāyapāhuḍa preserves teachings derived from the Purvas, mainly from the Kaṣāyaprābhṛta section of Dṛṣṭivāda,
• but it is not counted as “having” or “containing” the full 14 Purvas in original form.

Śvetāmbara tradition also agrees that the 14 Purvas are lost; they are known only through references in other āgamas, not as full surviving texts.

If you want to see the traditional list of the 14 Purvas, you can read more here