My understanding:
A website which is protected by https will send the public key within the certificate.
We use this public key to encrypt and send the "private key for the private key encryption", this "private key encryption" will be used to communicate between the client and server.
When and where does the TLS handshake happen?
What is the need for DH params (don't say to prevent Logjam i.e. is not my point, DH parameters are used to generate which/what key)?
Is the TLS handshake and DH parameters used to secure the certificate itself?