现(xiàn)在(zài) means ‘now’ or ‘current’. To be specific, it means the moment of speaking or a period of time around the speech time. For example,
Xiànzài wǒ zhèngzài chīfàn
Now I be doing eat
‘I am eating now.’
Xiànzài de niánqīngrén hěn xìngfú
Nowadays young people very happy
‘Young people in nowadays are very happy.’
最(zuì)近(jìn) means a period of time before the speech time or after the speech time or during the speech time.
Zuìjìn wǒ qù běijīng kāile huì
Recently I go to Beijing attended meeting
‘I went to Beijing and had a meeting recently.’
Zuìjìn wǒ zhèngzài běijīng kāihuì
Recently I be doing Beijing have a meeting
‘I am recently in Beijing for a meeting.’
Zuìjìn wǒ zhǔnbèi qù běijīng kāihuì
Recently I prepare go to Beijing have a meeting
I am prepare to go to Beijing for a meeting recently.
Therefore, you can see 现在 and 最近 can both mean a period of time around the speech time, but 现在 is used to express ‘nowadays’, with the opposite meaning ‘before’.