Clean the site of viruses

Remote work on the site. You need to clean the site of viruses, as well as “treat” the way the virus gets to the site, and then recently it often gets to the site. Before that, a couple of times managed to cure the site, but now it is so well hidden that my knowledge in the administration of the site is unfortunately not enough (Please help with this problem for a nominal fee of 1000 rubles). Thank you!