change theme to have ads in both sidebars?

Hello! I am so clueless about all of this! I have been blogging for two years now and can’t figure out how to effectively place ads on my blog. I see other blogs with beautiful ads above their headers, on both sidebars, etc. I don’t know if I need to change to a different theme, or what. Some have side by side ads in their sidebars too. My blog is https://www.thesavvystagerinc.com. I want it to look similar to this https://thriftydecorchick.blogspot.com/ I am absolutely desperate and at my wits end. I have blogged too long without moving to the next level. I really appreciate your help!