the processing is done on a cloudpage handler. Set up a Cloudpage as target for the link and write AMPScript there.
Each Emoji can point to the same Cloudpage, and the different emojis can deliver different parameter values.
Use CloudPagesURL() function to point to the cloudpage, adding additional parameters so that the link the cloudpage is appended with e.g. ?f=good, assuming you just call the type of feedback "good".
Also add the jobid, you always want to know which email the feedback was given for:
You links behind 3 emojis could basically be:
The link is automatically encrypted.
123 is the id of the cloudpage.
Assuming that you just want ONE feedback per jobid, make the subscriberkey AND the jobId field primary keys in your tracking DE and use upsertData.
On the Cloudpage you then need the functions requestparameter, upsertData and redirect:
SET @feedback = RequestParameter('f')
SET @jobid = RequestParameter('jid')
SET @subscriberkey = _subscriberkey /* automatically delivered with cloudpagesURL() links */
/* it is recommended to always timestamp your entries and add a source. just helps when processing data further. */
Code is from memory, but should be correct.
Hope this helps!