Adobe automated Service Agreement form

Hey All,

I've found some really valuable assistance on this platform previously and I'm hoping I can get the same again.

I am creating a digital service agreement for my company's client's. There are few bugs that I'm trying to fix and your insight would be greatly appreciated.

I need some Java code to pall data into field "Name_Of_Participant". The fields I want the data pulled from are "First_Name" and"Last_Name".

I got this from someone else on this platform;

{
this.getField("First_Name").valueAsString+" "+this.getField("Last_Name").valueAsString;
}

However I'm having trouble trying to work out how to execute this into the "Name_Of_Participant" field.

The other query I have is around signatures. I have implemented the option for my client's to give verbal consent over the phone (during the covid pandemic, it was all we could sit with until I worked out this form), however I want to be able to send the PDF form to my client for them to sign and send back. I know there is adobe fill and sign, however we have found that once we put our signature on it, it completely locks the document. I know there is a way, as I have seen other company's use it for their service agreements and they have certificates saved on an additional page of the PDF. How do I implement this?

I have a field in my form for each signature needed ("Signature1_es_:signer:signature", "Signature2_es_:signer:signature" and "Signature3_es_:signer:signature"). Signature 1 and 2 are to be signed by my client's and their rep's, signature 3 is signed by our staff.

Thanks so much is advance for any advice I can get!