Xiànzài hěnduō rén zài zhōngnián gǎiháng, zhuīqiú zìjǐ de mèngxiǎng.
Many people now change careers in middle age to pursue their dreams.
Tips
usage
改行 specifically means changing one's 行业 (trade or profession), not just changing jobs within the same field. Compare 跳槽 (to job-hop within the same industry).