Spending a few hours with a mastering engineer can smooth over the differences. But there's no rule that states a compilation of songs has to sound like an album. Mixtapes are fun for this very reason.

thank you for your reply.

i only used album because thats what im trying to go for with the recording. trying to record a cohesive album as a statement on my own

In that case--if you have a few hundred dollars--a qualified mastering engineer may be your best bet as far as getting all the levels similar, spectral balancing* (getting the lows, mids, and highs of the tracks to sound similar), and generally "smoothing over" any rough edges and outstanding frequencies.

He or she is not, however, a miracle worker. Recordings which have vastly different sonic signatures will still sound that way even after expensive mastering.

* not to be confused with phantom psychotherapy