Hi there,
You should be able to tie a secure two-handed knot and surgeons knot. You should also be able to instrument tie.
For closures: know how to close with simple interrupted sutures, vertical mattress and a subcuticular closure. The rest is just not that important.
Grab a copy of the Ethicon wound closure manual (can view this on-line)and you will know when to use what suture material under which conditions. Mostly know when to use absorbable versus non-absorbable suture material.
njbmd 🙂