Is it Possible to have a database table table of morethan 3000 fields
3000 optional fields today; 3001 tomorrow.  You are looking at all-to-frequent ALTER TABLE .. ADD COLUMN..

Keep the "common" columns as MySQL columns.  Put the rest into a JSON string.  Be aware that it is messy and inefficient to filter or sort on data buried inside a json string.

The EAV schema pattern has, in my opinion, worse drawbacks.