'In my opinion, national budget needs to be spent in more vital areas. If the development of arts costs governments too much money, other public services such as healthcare, security and infrastructure - all of which are more vital for a nation to function properly - may be underfunded. For instance, healthcare plays an essential role during the COVID-19 period. Countries that have an advanced healthcare system can overcome difficulty quickly and restart their economy. Also, arts seem to be luxury, even in the public, in some developing countries. However, 'artist' is also a profession and artists need to earn money by selling their work.'

Note: I corrected 'Furthermore' to 'However' in your last sentence because I think that's what you meant . The sentence seems to be on the opposite side of the argument to the rest of the paragraph, which would make 'However' more appropriate. 'Furthermore' would be appropriate if your last sentence were on the same side of the argument as the rest of the paragraph.

Hope that helps :)