Start with three decisions
Before creating a server, decide which Minecraft edition your group uses, whether the world will be private or public, and how important the world is. These choices affect the software you select, the way players connect, the security settings you need, and how frequently you should make backups.
Edition
Java players need a Java server. Bedrock players need a compatible Bedrock/Nukkit server. Do not choose based only on the device you own; ask every player which edition they use.
Access
A private friend server should normally use a whitelist. A public server needs moderation, rules, backups, and a plan for abuse reports.
Value of the world
If losing the world would matter, download backups regularly and especially before any software or configuration change.
Expected load
Player count, plugins, mods, entities, farms, and view distance all affect performance. Start small and increase complexity gradually.