Sales Page setup

Description

I have few tasks on a wrodpress site.
1stA malware invaded my site through a subdomain created for forms which are question ls for customers. I have a report of the malwares location on my cpanel but I don't know how to remove them without affecting other files. This malware is publishing lots of silly casino posts on my blog sections. 2nd.The logo on my site header is not coming out in the desktop version. It is showing in the mobile and tablet version. This is a minor issue. 3rd. The real job is I want to complete a payment page that is not working OR I think it would be better to just dump it and create a new one. I want to sell just a single item which is a guest post service. My geographical region has lots of payment integration problems. I'm presently thinking of individually hosting my order page differently on Wix, in the believe that they would automatically process payments. This is the part of the job I need to discuss and get done first.
Looking forward