1. Your HTML Body needs to use HTML if you want anything other than normal text.
2. Data can be made bold by using the same tags as you have mentioned.
3. Assuming you have a form which has the values you want (there can be other methods too but you didn't mention how you were geting the employee Name and such) this is an example:
Code:
Dim strBody As String
strBody = "Dear " & Me![Employee Name] & ": <br><br> Please find the attached Payslip. <br><br> The total is <b>" & Me!PayAmount & "</b><br><br>Regards<br><br><br>Finance Team"
.HTMLBody = strBody
(sorry for all of the <br> as HTML is not my strong suit and I'm sure there is a better way.)