Yes sales tax can be a bit of a burden for online sellers. It all stems from the Wayfair sales tax case. Basically states felt as though online sellers had an unfair advantage over brick and mortar sellers and started requiring that the online sellers collect sales tax if they sold enough (amounts and levels vary).
Some e-commerce platforms are marketplace facilitators which places the responsibility of sales tax on the platform as opposed to the individual seller. If you’re an individual sellers and choose to have your store on a sales channel that is NOT a marketplace facilitator then there are third-party apps like TaxJar, Avalara, etc. that will do much of this for you.