How do i remove salts e.g. buffers from my sample? I am using a reversed phase column and am getting poor retention for my compound?

Will salts like tris and carbonate bind to reversed phased columns?

And will the amount of salt in my sample affect the chromatogram?

None of these should be a problem. Your retention should be independent of the salt used - provided you use a buffer.
Tris and carbonate don't bind to RP columns.
If you have set up a proper buffer, the amount of salt in your sample should not be a problem.

What is the purpose of using buffers? Is it used to control the amount of ionization of the sample?

Can you please explain what you mean a proper buffer.
Thank you

For weak bases/weak acids:

the buffer controls the pH, the pH controls the degree of ionization of the analyte, and the degree of ionization of the analyte affects its retention.

A "proper" buffer (this is not an official term, by the way) is a buffer which has sufficient capacity to control your pH. In general, buffer capacity is related to the concentration of the buffer and to the pKa of the buffer relative to the pH (the closer, the better).

Thanks