Do you know if I can use an ERP software if I operate in the services industry?
Yes why not? There will be some modules that some mainstream and off the-shelf packages have that will not be applicable. For example, inventory management will not be that applicable.
However, you can either ignore some of the modules that your ERP have or you can have an ERP software developed for your company. A company that offers services such as accountants for example will have work in progress (WIP) instead of traditional physical stock which needs to be recognised based on the stage of the service that is being offered. So you can either search for an ERP specifically built for professionals that offer services or extend an existing ERP.